Process of preparing benzodiazepine compounds useful as antagonists of CCK or of gastrine

ABSTRACT

A benzodiazepine derivative of formula I, or a pharmaceutically acceptable salt thereof: ##STR1## wherein: (a) R 4  is an alkyl, cycloalkyl or aryl group. 
     (b) R 10  is chosen from halo, OH, CH 3 , OCH 3 , NR 11  R 12 , NO 2 , NHCHO, CO 2  H and CN, and R 11  and R 12  are independently selected from H and alkyl (C 1  -C 5 ) or together NR 11  R 12  form a cyclic structure II, ##STR2## wherein a is 1-6; and (c) R 2  is an aromatic 5- or 6-membered, substituted or unsubstituted heterocycle containing at least two heteroatoms of which at least one is nitrogen. 
     These compounds are gastrin and/or CCK-B receptor antagonists.

This application is a 371 of PCT/GB94/01859, filed Aug. 25, 1994.

This application is a 371 of PCT/GB94/01859, filed Aug. 25, 1994,published as WO95/06040 Mar. 2, 1995.

This invention relates to benzodiazepine derivatives which are useful asdrugs exhibiting antagonism at the gastrin and/or CCK-B receptor, and totheir production.

Many benzodiazepine derivatives have been described in the course ofdevelopment of psychotropic drugs which act as agonists at the"benzodiazepine receptor" in the central nervous system. More recentlybenzodiazepine derivatives have been described which act as antagonistsat the CCK-A (cholecystokinin-A) and CCK-B receptors. It was furtherreported that those compounds which were selective antagonists for theCCK-B receptor were able to reduce the secretion of gastric acid inresponse to the administration of pentagasuin (V J Lotti & R S L Chang,Eur J Pharmacol 1989, 162, 273-280). Examples of benzodiazepinederivatives which act as antagonists at the CCK-B receptor are disclosedin, for example, U.S. Pat. No. 4,820,834.

Most of the compounds of the present invention are novel. They differfrom the compounds described in U.S. Pat. No. 4,820,834, particularly inthe nature of the substituents at positions 1 and 5 of thebenzodiazepine nucleus. The present invention includes compounds ofsuperior pharmacological characteristics than those described in U.S.Pat. No. 4,820,834; preferred compounds of the invention have a higheraffinity for the CCK-B receptor and/or discriminate more selectivelybetween the CCK-B and CCK-A receptors than the previously describedcompounds.

The present invention provides a benzodiazepine derivative of formula X,or a pharmaceutically acceptable salt thereof: ##STR3## wherein: (a) R⁴is an alkyl, cycloalkyl or aryl group;

(b) examples of the substituent R¹⁰ include F, Cl, Br, I, OH, CH₃, OCH₃,NO₂, NHCHO, CO₂ H, CN and NR¹¹ R¹², where R¹¹ and R¹² are independentlyselected from H and alkyl (C₁ -C₅) or together with the N they form acyclic structure XI, ##STR4## and wherein a is 1-6.

(c) R² is an aromatic 5- or 6-membered substituted or unsubstitutedheterocycle containing at least two heteroatoms of which at least one isnitrogen.

Herein all `alkyl` and `cycloalkyl` groups are preferably of up to 8carbon atoms. When R⁴ is an aromatic residue it may be mono ordisubstituted, and it is preferably monocyclic.

Preferably the substituent R¹⁰ is at the meta position of the phenylring.

Preferably R² is an unsubstituted or monosubstituted heterocyclecontaining two heteroatoms of which at least one is nitrogen.

Most preferably R⁴ is tert-butyl or 2-, 3- or 4-methylphenyl.

Most preferably R² is selected from 2-pyrimidine, 4-pyrimidine,2-pyrazine, 6-pyridazine, 2-thiazole, 4-thiazole, 2-oxazole, 4-oxazole,3-pyrazole, 5-pyrazole, 3-isoxazole, 3-isothiazole, 2-imidazole,4-imidazole, 5-imictazole, 2-(N-methyl)imidazole, 4-(N-methyl)imidazoleand 5-(N-methyl)imidazole.

The compounds of this invention all have at least one stereogenic centreand so can exist as optical isomers. It should be understood that theseisomers, either separately or as mixtures, are included within the scopeof this invention. In preferred compounds according to the invention,the absolute configuration at the 3-position of the benzodiazepine ringis R (as shown in XII). ##STR5##

Amongst preferred compounds according to the invention are those listedbelow and salts thereof. Some of the compounds are exemplifiedhereinafter as indicated against the individual compounds concerned.

LIST A

1. N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)- 1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl) area (Example 3);

2. N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)- 1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 4);

3. N-((3RS)- 1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imldazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example1 );

4. N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethytaminophenyl)urea(Example2);

5. N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example7);

6.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example8);

7.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(4-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example10);

8. N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(4-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example11);

9.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example13);

10.N-((3RS)-1-tert-Butylcarbonytmethyl-2,3-dihydro-2-oxo-5-(3-pymzolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylamirtophenyl)urea;

11.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea;

12.N-((3RS)-1-tert-Butylcarbonyimethyl-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylamlnophenyl)urea;

13.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrimidinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea;

14.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrimidinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea;

15.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-pyrimidinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea;

16.N-((3RS)-1-tert-Butylcarbonyimethyl-2,3-dihydro-2-oxo-5-(4-pyrimidinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea;

17.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example5);

18.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example6);

19.N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrollidinyl)phenyl)urea(Example9);

20.N-((3RS)-2,3-Dihydro-5-(4-imidazolyl)-1-(4-methylphenylcarbonylmethyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example12).

The compounds of the invention can be prepared according to the generalroute outlined below (Scheme 1).

Where R² contains NH as part of the heterocycle a suitable protectinggroup may be required for pan or all of the synthetic route outlined inScheme 1, and a final deprotection step may be required. Theaminobenzoyl starting material, if previously reported, was preparedusing literature routes. Previously unreponed starting materials wereprepared using standard methodology, the details of which are describedbelow.

Among the reports of benzodiazepine derivatives acting as CCK-A, CCK-Bor gastrin receptor antagonists the most frequently encounteredsubstitution pattern is the3-acylamino-5-aryl-2,3-dihydro-1H,-1,4-benzodiazepin-2-one with avariety of substituents at N-1. Previously described syntheses of3-amino-5-aryl substituted 2,3-dihydro-1H-1,4-benzodiazepin-2-oneseither introduce the 3-amino function by nitrosation and reduction of a3-unsubstituted benzodiazepine or start with an α-alkylthioglycinederivative and cyclise this to give directly a protected3-aminobenzodiazepine. The nitrosation/reduction route fails when the5-aryl substituent is other than (substituted) phenyl while thealkylthioglycine route involves the use of unpleasant alkylmercaptansand requires the mediation of highly toxic mercuric salts. The processof this invention avoids the use of environmentally unacceptablereagents and is generally applicable to any 5-aryl substituent. ##STR6##

The present invention provides a process for the production ofbenzodiazepines of general formula V or pharmaceutically active saltsthereof which comprises the coupling reaction of an-optionallysubstituted N-protected α-(1-benzotriazolyl)glycine derivative (II) withan aromatic or heterocyclic amino ketone (III), followed by reaction ofthe intermediate (IV) with ammonia and then an acid catalysedcyclisation of the resultant amino-ketone ##STR7## wherein: R² is anoptionally substituted aromatic carbocyclic or heterocyclic group;

R⁸ is a lower alkyl (C₁ -C₆, linear or branched), a cycloalkyl (C₃ -C₈),or an optionally substituted aralkyl, aryl or heteroaryl group;

R⁹ is H, lower alkyl (C₁ -C₆, linear or branched) or CH₂ COR⁴ where R⁴is an alkyl (preferably C₁ -C₆, linear or branched), a cycloalkyl(preferably C₃ -C₈), or an optionally substituted aryl, heteroaryl orsaturated heterocyclic group;

X¹ is H, alkyl (C₁ -C₃), alkyloxy (C₁ -C₃), F, Cl or Br;, and

Y is --O--, --NH-- or a single bond.

Preferably, R⁸ is a lower alkyl (C₁ -C₆, linear or branched), acycloalkyl (C₃ -C₈), or an optionally substituted benzyl, phenyl orheteroaryl group;

R⁹ is H or lower alkyl (C₁ -C₆, linear or branched);

X¹ is H; and

Y is --O--.

The process of the invention can of course produce compounds of formulaX above, including the specified preferred embodiments thereof.

Herein aryl means aromatic cyclic and includes both carbocyclic andheterocyclic aromatics.

Benzodiazepines obtainable by the process of the invention, or readilyprepared from products of said process, include those of formula I andsalts thereof: ##STR8## wherein: (a) --NHR¹ is an alkyl (C₁ -C₆, linearor branched), cycloalkyl (C₃ -C₈), or optionally substituted aralkyl,aryl or heteroaryl carbamate group or R¹ is H or --CONHR⁵ where R⁵ is analkyl (C₁ -C₆, linear or branched), a cycloalkyl (C₃ -C₈), or anoptionally substituted aromatic carbocyclic or heterocyclic or aralkylgroup;

(b) R² is an optionally substituted aromatic carbocyclic or heterocyclicgroup; and

(c) R³ is H, alkyl (C₁ -C₆, linear or branched), or --CH₂ COR⁴ where R⁴is a lower alkyl (C₁ -C₆, linear or branched), cycloalkyl (C₃ -C₈) or anoptionally substituted aryl (e.g. phenyl), heteroaryl or saturatedheterocyclic group.

Preferably R¹ is H or tert-butyloxycarbonyl, methyloxycarbonyl,ethyloxycarbonyl or benzyloxycarbonyl or --CONHR⁵.

Preferably R² is pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl,thiazolyl, isothiazolyl, methyl-imidazolyl, oxazolyl, isoxazolyl,optionally protected pyrazolyl or imidazolyl or optionally substitutedphenyl.

Preferably R³ is H or CH₂ COR⁴.

Preferably R⁴ is tert-butyl, cycloalkyl C₃ -C₇ or 2-, 3- or 4-methylphenyl.

Preferably R⁵ is a phenyl group substituted at the 3-position with asubstituent selected from F, Cl, Br, OH, OCH₃, NO₂, CH₃, CO₂ H, SO₃ H,tetrazolyl and NR⁶ R⁷ where R⁶ and R⁷ are independently H, C₁ -C₃ alkyl,a recognised nitrogen protecting group or together form a 3-7 reinsertedring with nitrogen.

Most preferably R² is 2-, 3- or 4-substituted pyridyl or phenyl.

Most preferably R⁵ is a phenyl group substituted in the 3-position witha substituent selected from CH₃ and NR⁶ R⁷, where R⁶ and R⁷ arepreferably independently selected from H, CH₃, ethyl, formyl,tert-butyloxycarbonyl, and benzyloxycarbonyl or together are analkylidene chain which forms a 3-6 membered ring with the nitrogen.

The compounds of formulae V and I and theft salts all have at least onestereogenic centre and so can exist as optical isomers. It should beunderstood that the preparation of these isomers, either separately oras mixtures, is included within the scope of this invention. Compoundsof formulae X, V and I can form salts with inorganic or organic acidsor, in some cases, bases. Examples of such salts would includechlorides, sulphates and acetates, or sodium and potassium salts. Saltsand their preparation should also be understood to be included withinthe scope of this invention.

Compounds of formulae X, V and I and their salts include compounds whichcan act as CCK-B and/or gastrin receptor antagonists and which may beused as drugs for the treatment of diseases induced by the failure of aphysiological function controlled by gastrin, such as gastric andduodenal ulcers, gastrins, reflux esophagatis, gastric and coloncancers, and Zollinger-Ellison syndrome; there may be no side effectsarising from CCK-A receptor interaction. The drugs may be used for thetreatment of diseases induced by the failure of physiological functioncontrolled by the central CCK-B receptor (e.g. for the reduction ofanxiety or for appetite regulation).

Amongst preferred compounds of formula V or I are those listed below andsalts thereof. The compounds are exemplified hereinafter to demonstratethe scope and utility of the process herein described, as indicatedagainst the individual compounds.

LIST B

1(3RS)-(Ethoxycarbonyl)amino-2,3-dihydro-5-(2-pyridyl)-1-H-4-benzodiazepin-2-one(Example 16)

2(3RS)-(Ethoxycarbonyl)amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one(Example 17)

3(3RS)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-(1H)-1,4-benzodiazepin-2-one(Example 18)

4(3R)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-(1H)-1,4-benzodiazepin-2-one(Example 19)

5(3S)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-(1H)-1,4-benzodiazepin-2-one(Example 20)

6N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-((3-dimethylamino)phenyl)urea(Example 22)

7N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-(N-formyl-N-methylamino)phenyl)urea(Example 25)

8N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-((3-methylamino)phenyl)urea(Example 26)

9N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-aminophenyl)urea(Example 28)

10(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one(Example 1C)

11(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one(Example 1D)

12(3RS)-3-Amino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one(Example 1E)

13N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 1F)

14N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 2)

15(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-thiazolyl)-1H-1,4-benzodiazepin-2-one(Example 3B)

16(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-thiazolyl)-1H-1,4-benzodiazepin-2-one(Example 3C)

17(3RS)-Amino-1-tert-butylcarbonytmethyl-2,3-dihydro-5-(2-thiazolyl)-1H-1,4-benzodiazepin-2-one(Example 3D)

18N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 3E)

19N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 4)

20(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-2-one(Example 5D)

21(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-2-one(Example 5E)

22(3RS)-Amino-1-tert-butylcarbonytmethyl-2,3-dihydro-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-2-one(Example 5F)

23N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 5G)

24N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 6)

25(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-2-yl)-1H-1,4-benzodiazepin-2-one(Example 7E)

26(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-2-yl)-1H-1,4-benzodiazepin-2-one(Example 7F)

27N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-2-yl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 7G)

28N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 7H)

29N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-2-yl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea (Example 8A)

30N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 8B)

31N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-2-yl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrrolidyl)phenyl)urea(Example 9B)

32N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrrolidyl)phenyl)urea(Example 9C)

33(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-4-yl)-1H-1,4-benzodiazepin-2-one(Example 10F)

34(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-4-yl)-1H-1,4-benzodiazepin-2-one(Example 10G)

35N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(1-((2-trimethylsilyl)ethoxy)methyl)imidazol-4-yl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 10H)

36N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 10I)

37N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(1-((2-trimethylsilyl)ethoxy)methyl)-imidazol-4-yl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea

38N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 11B)

39(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(1-((2-trimethylsilyl)ethoxy)methyl)pyrazol-3-yl)-1H-1,4-benzodiazepin-2-one(Example 13G)

40(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(1-((2-trimethytsilyl)ethoxy)methyl)pyrazol-5-yl)-1H-1,4-benzodiazepin-2-one(Example 13H)

41(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(1-((2-(trimethylsilyl)ethoxy)methyl)pyrazol-3-yl)-1H-1,4-benzodiazepin-2-one(Example 13I)

42(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(1-((2-(trimethylsilyl)ethoxy)methyl)pyrazol-5-yl)-1H-1,4-benzodiazepin-2-one(Example 13J)

43(3RS)-Amino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-2-one(Example 13K)

44 N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-3-yl-N'-(3-methylphenyl)urea(Example 13L)

45(3RS)-Benzyloxycarbonylamino-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-2-one(Example 32)

46(3RS)-Benzyloxycarbonylamino-1tert-Butylcarbonylmethyl-2,3-dihydro-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-2-one(Example 33)

47N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Example 34)

48N-(3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl-N'-(3-(1-piperidinyl)phenyl)urea(Example 40)

49(3RS)-tert-Butyloxycarbonylamino-2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodiazepin-2-one(Example 41)

50((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Example 42)

51N-((3R)-1-tert-Butylcarbonytmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylaminophenyl)urea(Example 52) and the N-((3R)-isomers of compounds 7 and 8 above.

Preferred processes of this invention are outlined in Scheme 2: ##STR9##where R² is as defined above; R⁸ is alkyl (C₁ -C₆), cycloalkyl (C₃ -C₈),optionally substituted benzyl or optionally substituted aryl; R⁹ is H oralkyl (C₁ -C₆); X¹ is H, alkyl (C₁ -C₃), alkyloxy (C₁ -C₃) or halide;and Y is --O--, --NH-- or a single bond. Preferably R⁸ is methyl, ethyl,tert-butyl or benzyl; R⁹ is H or methyl; X¹ is H; and Y is --O--.

In step (i) a protected α-benzotriazolylglycine derivative II iscondensed with an amine III. This may be achieved using any of themethods known to effect amide bond formation. The acid is eitherconverted into a reactive derivative (for example the acid chloride bytreatment with e.g. thionylchloride or oxalyl chloride, a mixedanhydride by reaction with e.g.-ethyl chloroformate or isobutylchloroformate, or the symmetrical anhydride by treatment with e.g.acetic anhydride or dicyclohexylcarbodiimide) or it is premixed with theamine III and the mixture is treated with a condensing agent. Such anagent may be chosen from, but is not limited to, a carbodiimide (forexample dicyclohexyl carbodiimide, N-ethyl-N'-dimethylaminopropylcarbodiimide), BOP-CI (bis(2-oxo-3-oxazolidinyl) phosphoryl chloride),EEDQ (2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline), PyBroP(bromo-tris-pyrrolidino- phosphonium hexafluorophosphate), and HBTU(O-benzotriazolyl-tetramethylisouronium hexafluorophosphate). With someof these reagents it is beneficial to add a catalyst. These catalystsare generally known, and include for example, DMAP(4-dimethylaminopyridine), hydroxybenzotriazole, and pentafluorophenol.It will also, on occasion, be found necessary to add a base to thereaction. In these cases the base is usually an organic amine, forexample triethylamine or N-methylmorpholine. The solvent for thereaction is any organic solvent or mixture of solvents which does notreact with any of the reagents used. Suitable solvents include but arenot limited to dichloromethane, chloroform, ethyl acetate,dimethylformamide, tetrahydrofuran and toluene. Preferably the reactionis performed by treating a mixture of II and III with a carbodiimide,most preferably dicyclohexylcaxbodiimide orN-ethyl-N'-dimethylaminopropyl carbodiimide, in the presence of DMAP ascatalyst and with dichloromethane as solvent. Depending on the exactnature of the reagents used and the substituents present the temperatureat which the reaction is carried out can be between -80° C. and theboiling point of the solvent used. Preferably it is between -20° C. andthe boiling point of the solvent, and most preferably it is between -5°C. and 25° C.

The amide IV can be purified, for example by crystallisation orchromatography, but in general this is not necessary, in which case itis preferable to use the crude product IV in step (ii) directly.

In step (ii) the benzotriazolylamide IV is first reacted with ammonia,either in liquid ammonia without a solvent or using a solution ofammonia in a solvent. The solvent is either water or preferably anorganic solvent such as an alcohol, THF, diethyl ether, or dioxan. Morepreferably it is an alcohol, and most preferably methanol or ethanol ora mixture based on methanol or ethanol (such as industrial methylatedspirit).

In the second part of step (ii) the product of this reaction withammonia is cyclised to give the benzodiazepine V. Preferably this isperformed by treatment with acid. More preferably this acid is anorganic carboxylic acid, and most preferably acetic acid. It may also beadvantageous to add ammonium acetate. When the acid is a liquid it isnot always necessary to use a solvent for this reaction. When the acidis a solid, or is a liquid in which the other reaction component doesnot dissolve, then a solvent can be used. This solvent is any organicsolvent. In the preferred case where the acid is acetic acid then nosolvent is necessary and it is preferred that none be added.

Each part of step (ii) may be carried out at any temperature between-80° C. and the boiling point of the solvent, and preferably between-20° C. and the boiling point of the solvent. Most preferably the firstpart is performed between -5° C. and 30° C., and the second part isperformed between 10° C. and 30° C.

Often benzodiazepine V will not be the final active CCK or gastrinreceptor antagonist, but a useful intermediate for the synthesis of sucha compound. A preferred such transformation is illustrated in Schemes 3and 4. ##STR10## where R⁴ is described above; and X² is chosen from ahalogen atom (chloride, bromide, iodide) or an organic sulphonate (forexample methanesulphonate, tosylate, trifluoromethanesulphonate).Preferably X² is a halogen and most preferably bromide.

In step (iii) the benzodiazepine VI is alkylated. This requires the useof a base to deprotonate the nitrogen atom which is involved in thereaction. The base can either be added to VI to preform the deprotonatedspecies before addition of the alkylating agent or it can be added to amixture of VI and the alkylating agent. The base used can be any strongbase, and is preferably a metal hydride (e.g. sodium or potassiumhydride), a metal alkoxide (e.g. sodium methoxide, potassium t-butoxide,a metal amide (e.g. sodium amide, NaNH₂), or a metal hydroxide (e.g.sodium hydroxide). Most preferably it is sodium hydride. The solvent forthe reaction is any solvent compatible with the base used. Preferably itis a dipolar aprotic solvent and most preferably it isdimethylformamide. An alternative preferred solvent is a mixture ofwater and an organic solvent such as toluene. This mixture of solventsrequires the inclusion of a phase-transfer catalyst (which can be chosenfrom any known phase-transfer catalyst) and is best suited to the use ofmetal hydroxides as base. The reaction is performed at any temperaturebetween -80° C. and the boiling point of the solvent and preferablybetween -10° C. and 30° C.

In step (iv) the carbamate protecting group is removed. The conditionsappropriate will depend on the nature of R⁸ and are generally wellknown. Examples of such conditions are the use of strong acids (e.g.HCl, HBr, CF₃ CO₂ H), strong bases (e.g. NaOH), and hydrogenolysis overa catalyst (e.g. Pt-on-C, Pd-on-C). One preferred set of conditionswhich is applicable for most of the preferred examples of R⁸ is the useof HBr in dichloromethane. ##STR11## where R⁵ is as described above.

Racemic amine VII can be resolved into two enantiomers by any methodknown for the resolution of amines. Preferably it is resolved bycrystallisation in the presence of a single enantiomer of a chiral acid.This acid may be chosen from any of the known chiral acids, for exampletartaric acid, lactic acid, and camphorsulphonic acid. Preferably theacid is mandelic acid. Most preferably it is (R)-mandelic acid, in whichcase when R² is 2-pyridyl, the salt with the (R)-aminobenzodiazepinecrystallises.

The amine VIII, and preferably a single enantiomer of VIII, can bereacted with an isocyanate R⁵ NCO to give a urea IX. This reaction isbest performed in a solvent. The solvent is preferably a common organicsolvent which does not react with the reaction components. Examples ofsuch solvents are toluene, THF, dichloromethane and ethyl acetate. Mostpreferably the solvent is a chlorinated hydrocarbon such asdichloromethane.

The reaction can be performed at any temperature between -80° C. and theboiling point of the solvent. Preferably it is performed between -20° C.and the boiling point of the solvent, and most preferably between -10°C. and 30° C.

When the heterocyclic amino ketone, III, contains a reactive nitrogenatom, this atom may be protected by a suitable aromatic nitrogenprotecting group (such as trimethylsilylethoxymethyl) during thesynthetic steps (i) to (vi). This group can be unmasked at a late stageor preferably after steps (i) to (vi) to provide the requiredbenzodiazepine derivative.

The invention will now be further illustrated with the followingspecific, non-limiting examples. In these examples room temperature isdenoted by r.t.

EXAMPLE 1N-((3RS)-1-tert-Butycarbonylmethyl-2,3-dihydro-2-oxo-5-2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-3-1-N'-3-methylphenylurea (Compound 3) ##STR12## 1A 2-Aminophenyl 1-methyl-2-imidazolylketone

The title compound was prepared according to the method of Fryer et al.(Synth Commun 1993, 23, 985) and was isolated as yellow needles (1.72 g,85%) from DCM/hexane (m.p. 88°-90° C.; Lit. 91°-92° C.).

1B 2-(1-Benzotriazolyl)-2-benzyloxycarbonylamino acetic acid

The title compound was prepared according to the method of Katritsky (JOrg Chem 1990, 55, 2206) in 81% yield.

1C(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one

The amino ketone of example 1A (1.015 g, 5 mmol) and the benzotriazolederivative of example 1B (2.28 g, 7 mmol) were suspended in DCM (20 ml)at 0° C. and treated portionwise with water soluble carbodiimide (1.34g, 7 mmol) and DMAP (100 mg). The mixture was allowed to warm to r.t.over 1/2 h and then poured into 5% KHCO₃ and extracted with EtOAc (2×50ml). The combined extracts were washed with brine, dried over Na₂ SO₄and evaporated. The residue was chromatographed on silica (eluant 75/25,v/v, EtOAc/hexanes) to provide a yellow foam (2.20 g, 86%) which wastaken up in an ice-cold saturated solution of ammonia in methanol (30ml), stoppered and stirred at r.t. for 1 h. The mixture was thenevaporated and treated with a 10% solution of ammonium acetate in aceticacid at r.t. 1 h. The resultant mixture was evaporated and the residuepartitioned between EtOAc and 1M NaOH. The organic portion was filtered(Whatman 1PS phase separator) and evaporated and the productcrystallised as a white solid from EtOAc/hexane (905 mg, 47% overall).

¹ H NMR (270 MHz, CDCl₃) δ 9.94 (1H, br.s.); 7.5-7.0 (m, 10H); 6.68 (2H,m); 5.2-5.0 (3H, m); 3.92 (3H, s) ppm.

1D(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 1D (850 mg, 2.174 mmol) was taken up indry DMF (8 ml) at 0° C. under N₂. The solution was treated with NaH (85mg, 80% disp. in. oil, 1.3 eq) with stirring for 1 h. 1-Bromopinacolone(506 mg, 1.3 eq) was added and stirring continued at r.t. 1 h. Themixture was evaporated and the residue partitioned between brine andEtOAc. The organic portion was filtered (Whatman 1 PS, phase separator)and evaporated. The residue was chromatographed on silica gel (eluantEtOAc) and crystallised from EtOAc/hexanes (610 mg, 58%).

¹ H NMR (270 MHz, CDCl₃) δ 7.62 (1H, m); 7.50 (1H, m); 7.4-7.0 (9H, m);6.64 (1H, d, J=8 Hz); 5.41 (1H, d, J=8 Hz); 5.16 (2H, s); 5.02 (1H, d,J=17 Hz); 4.32 (1H, d, J=17 Hz); 3.93 (3H, s); 1.22 (9H, s) ppm.

1E(3RS)-3-Amino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 1D was dissolved in DCM (20 ml) at 0° C.The solution was saturated with dry HBr gas, stoppered and stirred at 0°C. for 2 h. The mixture was evaporated and partitioned between 1M HCland ether. The aqueous portion was basified and extracted with CHCl₃(3×50 ml). The chloroform extracts were filtered (Whatman 1PS paper) andevaporated to provide a pale yellow foam (420 mg, 96%).

¹ H NMR (270 MHz, CDCl₃) δ 7.62 (1H, m); 7.48 (1H, m); 7.26 (1H, m);7.1-7.0 (3H, m); 5.08 (1H, d, J=16 Hz); 4.61 (1H, s); 4.29 (1H, d, J=16Hz); 4.02 (3H, s); 2.37 (2H, br.s.); 1.25 (9H, s) ppm.

1FN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The benzodiazepine of example 1E (210 mg, 0.5915 mmol) was dissolved inDCM (3 ml) and treated with m-tolyl isocyanate (85 μl, 0.65 mmol) atr.t. 1 h. The mixture was cooled to 0° C. and diluted with hexane (8 ml)and the resultant precipitate collected to provide the title compound(250 mg, 87%).

¹ H NMR (270 MHz, CD₃ OD) δ 7.7-7.1 (9H, m); 6.80 (1H, d, J=8.5 Hz);5.48 (1H, s); 5.08 (1H, d, J=16.5 Hz); 4.81 (1H, d, J=16.5 Hz); 3.94(3H, s); 2.28 (3H, s); 1.25 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =487.4.

EXAMPLE 2N-((3RS)-1-tert-Butylcarbonytmethyl-2,3-dihydro-2-oxo-5-(2-(1-methyl)imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylammophenyl)urea##STR13##

The benzodiazepine of example 1E (210 mg, 0.5915 mmol) was added as asolution in DCM (5 ml), to a mixture of m-(dimethylamino)benzoic acid(305 mg), triethylamine (360 μl) and diphenylphosphoryl azide (0.71 g),that had been heated under reflux under nitrogen for 5 h, thenevaporated. The resultant mixture was stirred at r.t. 2 h, thenevaporated and chromatographed (eluant EtOAc→6% MeOH/EtOAc). The productwas recrystallised from MeCN to provide a colourless solid (254 mg,83%).

¹ H NMR (270 MHz, CDCl₃) δ 7.63 (1H, d, J =8 Hz); 7.48 (1H, m); 7.3-6.9(8H, m); 6.42 (2H, m); 5.61 (1H, d, J=7.5 Hz); 4.95 (1H, d, J=17.7 Hz);4.28 (1H, d, J=17.7 Hz); 3.96 (3H, s); 2.90 (6H, s); 1.22 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =516.5.

EXAMPLE 3N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Compound 1) ##STR14## 3A 2-Aminophenyl 2-thiazolyl-ketone

This was prepared over three steps following the method of Kaish et al.(J Heterocyclic Chem 1975, 12, 49).

3B(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-thiazolyl)-1H-1,4-benzodiazeodiazepin-2-one

This was prepared following the method of example 1C using 2-aminophenyl2-thiazolyl ketone (2.04 g, 10 mmol). The product was afforded as paleyellow crystals after crystallisation with EtOAc (1.96 g, 50%).

¹ H NMR (270 MHz, CDCl₃) δ 8.20 (1H, s); 8.00 (2H, m); 7.70-7.30 (9H,m); 6.70 (1H, d, J=8 Hz); 5.55 (1H, d, J=8 Hz); 5.25 (2H, s).

3C(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-triazolyl)-1H-1,4-benzodiazepin-2-one

The title compound was prepared from the benzodiazepine of example 3B(1.96, 5 mmol) following the method of example 1D. The resultant productwas purified by flash chromatography on silica gel (eluant 50%EtOAc-hexane Fr.) to afford the title compound as a pale yellow solid(2.00 g, 82%).

¹ H NMR (270 MHz, CDCl₃) δ 7.80-7.05 (11H, m); 6.55 (1H, d, J=8 Hz);5.45 (1H, d, J=8 Hz); 5.05 (2H, s); 4.95 (1H, d, J=17 Hz); 4.35 (1H, d,J=17 Hz); 1.20 (9H, s).

3D(3RS)-3-Amino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-thiazolyl)-1H-1,4-benzodiazepin-2-one

The title compound was prepared using the benzodiazepine of example 3C(1.00 g, 2.04 mmol) following the method of example 1E. After work-upthe resultant yellow solid was used without further purification (300mg, 41%).

¹ H NMR (270 MHz, CDCl₃) δ 7.70-7.05 (6H, m); 5.00 (1H, d, J=17 Hz);4.65 (1H, s); 4.35 (1H, d, J=17 Hz); 2.40 (2H, s); 1.20 (9H, s).

3EN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The title compound was prepared following the method of example 1F fromthe benzodiazepine of example 3D (150 mg, 0.42 mmol) and m-tolylisocyanate (77 μl, 0.6 mmol) in DCM. By adding hexane Fr. to thereaction mixture the title compound was afforded as pale yellow crystals(127 mg, 62%).

¹ H NMR (270 MHz, CDCl₃) δ 7.75-7.10 (10H, m); 7.60 (1H, d, J=8 Hz);6.65 (1H, d, J=8 Hz); 6.00 (1H, d, J=8 Hz); 5.00 (1H, d, J=17 Hz); 4.35(1H, d, J=17 Hz); 2.30 (3H, s); 1.25 (9H, s).

M.S. (+ve FAB) M+H!⁺ =490.3.

EXAMPLE 4N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-thiazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Compound 2) ##STR15##

The title compound was prepared following the method of example 2 fromthe benzodiazepine of example 3D (150 mg, 0.42 mmol). The crude productwas purified by flash chromatography on silica gel (eluant 75%EtOAc-hexane Fr.) and crystallised from acetonitrile to afford the titlecompound as a pale yellow solid (80 mg, 37%).

¹ H NMR (270 MHz, CDCl₃) δ 8.00-7.10 (10H, m); 6.62 (1H, d, J=8 Hz);6.58 (1H, d, J=8 Hz); 5.95 (1H, d, J=8 Hz); 5.05 (1H, d, J=17 Hz); 4.55(1H, d, J=17 Hz); 3.05 (6H, s); 1.35 (9H, s).

M.S. (+ve FAB) M+H!⁺ =519.3.

EXAMPLE 5N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Compound 17) ##STR16## 5A Phenacyl pyrazine

Phenacyl pyrazine was prepared from methyl pyrazine and methyl benzoateas described by Behun and Levine (J Am Chem Soc 1959, 81, 5157) in 68%isolated yield (chromatography on silica-eluant 60% EtOAc in hexanes).

5B 2-Phenyl-3-pyrazinyl indole

The ketone of example 5A (3.62 g, 18.4 mmol) and freshly distilledphenyl hydrazine (1.9 ml, 18.4 mmol) were stirred together in refluxingtoluene under Dean-Stark conditions for 1 h, after which time no ketoneremained as evidenced by t.l.c. Zinc (II) chloride (272 mg, 2 mmol) wasadded and reflux continued for 3 h. The mixture was evaporated andpartitioned between EtOAc and brine and the organic portion filtered(Whatman 1PS phase separator) and evaporated. The residue waschromatographed on silica gel (eluant 45% EtOAc in hexanes) to providethe title compound as a fluffy tan solid (2.0 g, 40%).

¹ H NMR (270 MHz, CDCl₃) δ 9.45 (1H, br.s.); 8.52 (1H, t, J=1.5 Hz);8.43 (1H, d, J=1.5 Hz); 8.23 (1H, d, J=1.5 Hz); 8.10 (1H, m); 7.4-7.2(8H, m) ppm.

5C 2-Amino benzoyl pyrazine

The indole of example 5B (813 mg, 3 mmol) was treated with CrO₃ inacetic acid as described for the 3-pyridyl analogue by Ockenden andSchofield (J Chem Soc 1953, 3440), to provide the benzyl amide of thetitle compound in 40% yield (isolated by chromatography-eluant 55% EtOAcin hexanes). The product (370 mg, 1.22 mmol) was taken up in ethanol (4ml) and treated with 5M KOH (10 ml) at 70° C. for 4 h. The mixture wasdiluted with brine (50 ml) and extracted with CHCl₃ (×3). The combinedextracts were filtered (Whatman 1PS, phase separator), evaporated andchromatographed on silica gel (eluant 40% EtOAc in hexanes) to providethe title compound as a yellow crystalline solid (120 mg, 60%).

¹ H NMR (270 MHz, CDCl₃) δ 9.02 (1H, d, J=1.7 Hz); 8.71 (1H, d, J=1.7Hz); 8.65 (1H, t, J=1.7 Hz); 7.63 (1H, dd, J₁ =8 Hz, J₂ =1.5 Hz); 7.33(1H, dt, J_(t) =8 Hz, J_(d) =1.5 Hz); 6.75 (1H, d, J=8 Hz); 6.61 (1H,dt, J_(t) =8 Hz, J_(d) =1.5 Hz); 6.40 (2H, br.s.) ppm.

5D(3RS)-3-Benzyloxycarbonylamino-2,3-dihdro-5pyrazin-1H-1,4-benzodiazepin-2-one

The title compound was prepared from the amino ketone of example 5C andthe benzotriazole derivative of example 1B as described in example 1C.The product was isolated by chromatography on silica gel (eluant 85%EtOAc in hexanes) in 58% yield.

¹ H NMR (270 MHz, CDCl₃) δ 9.78 (1H, br.s.); 9.28 (1H, d, J=1.5 Hz);8.61 (1t, J=1.5 Hz); 8.55 (1H, d, J=1.5 Hz); 7.5-7.1 (8H, m); 7.06 (1H,d, J=8 Hz); 6.90 (1H, d, J=8 Hz); 5.40 (1H, d, J=8 Hz); 5.18 (2H, s).

5E(3RS)-3-Benzyloxcarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-pyrazinyl-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 5D (120 mg, 0.31 mmol) was taken up in dryDMF (4 ml) at 0° C. under nitrogen. Sodium hydride (13 mg, 80% disp. inoil) was added to the stirring mixture followed after 45 min. by1-bromopinacolone. The mixture was stirred at r.t. 1 h, evaporated andchromatographed on silica gel (eluant, 75% EtOAc in hexanes) to providea colourless film (146 mg, 97%).

¹ H NMR (270 MHz, CDCl₃) δ 9.37 (1H, d, J=1.3 Hz); 8.64 (1H, d, J=1.3Hz); 8.55 (1H, t, J=1.4 Hz); 7.6-7.2 (8H, m); 7.14 (1H, d, J=8 Hz); 6.74(1H, d, J=8 Hz); 5.55 (1H, d, J=8 Hz); 5.14 (2H, s); 4.95 (1H, d, J=16Hz); 4.66 (1H d, J=16 Hz); 1.23 (9H, s) ppm.

5F(3RS)-3-Amino-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-pyrazinyl-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 5E was deprotected using HBr in DCM asdescribed in example 1E. The brown oil product was not homogeneous butwas used without purification in the next reactions.

5GN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The title compound was prepared from the benzodiazepine of example 5F(0.15 mmol), by treating a DCM solution (3 ml) with m-tolyl isocyanateat 0° C. After 1 h, the mixture was evaporated and chromatographed onsilica gel (eluant 75% EtOAc→90% EtOAc in hexanes) to provide acolourless solid (44 mg, 61% for two steps).

¹ H NMR (270 MHz, CDCl₃) δ 9.37 (1H, d, J =1 Hz); 8.62 (1H, d, J=1.5Hz); 8.54 (1H, t, J=1.5 Hz); 7.54 (1H, t, J=8 Hz); 7.4-7.0 (8H, m); 6.82(1H, d, J=7 Hz); 5.77 (1H, d, J=8 Hz); 4.89 (1H, d, J=18 Hz); 4.66 (1H,d, J=18 Hz); 2.26 (3H, s); 1.20 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =485.2.

EXAMPLE 6N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyrazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Compound 18) ##STR17##

The title compound was prepared as described in example 2 from thebenzodiazepine of example 5F, it was purified by chromatography onsilica gel (eluant 80% EtOAc/hexanes→100% EtOAc) to provide a colourlesssolid (34 mg, 44%).

¹ H NMR (270 MHz, CDCl₃) δ 9.37 (1H, d, J=1.5 Hz); 8.62 (1H, d, J=1.5Hz); 8.54 (1H, t, J=1.5 Hz); 7.50 (1H, dt, J_(t) =8 Hz, J_(d) =1.5 Hz);7.4-7.0 (6H, m); 6.89 (1H, m); 6.51 (1H, d, J=8 Hz); 6.43 (1H, d, J=8Hz); 5.77 (1H, d, J=8 Hz); 4.87 (1H, d, J=17.5 Hz); 4.63 (1H, d, J=17.5Hz); 2.90 (6H, s); 1.19 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =514.3.

EXAMPLE 7N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl-N'-(3-methylphenyl)urea(Compound 5) ##STR18## 7A2-(Hydroxy-(2-nitrophenyl))methyl-N,N-dimethylimidazole-1-sulphonamide

N,N-Dimethylimidazole-1-sulphonamide (Chadwick & Ngochindo, J Chem SocPerkin Trans I 1984, 481) (4.0 g, 23.2 mmol) was taken up in dry THF (40ml) at -70° C. under nitrogen. n-Butyl lithium (16 ml, 1.6M solution inhexanes) was added dropwise and the mixture stirred at -70° C. for 20min. 2-Nitrobenzaldehyde (5.6 g, 37 mmol) was added in THF (20 ml) andthe mixture allowed to warm to r.t. over 2 h. The mixture was evaporatedand partitioned between 5% KHCO₃ and EtOAc. The organic portion waswashed with brine, filtered (Whatman 1PS, phase separator), evaporatedand chromatographed on silica gel (eluant 85% EtOAc in hexanes) toprovide the title compound as a yellow foam (3.31 g, 44%).

¹ H NMR (270 MHz, CDCl₃) δ 8.10 (1H, d, J=8 Hz); 7.95 (1H, d, J=8 Hz);7.72 (1H, t, J=8 Hz); 7.54 (1H, t, J=8 Hz); 7.21 (1H, s); 6.85 (1H, s);6.80 (1H, d, J=2 Hz); 4.45 (1H, d, J=2 Hz); 3.02 (6H, s) ppm.

7B 2-(2-Nitrobenzoyl)imidazole

The sulphonamide of example 7A (3.30 g, 10.12 mmol) was taken up inglacial acetic acid (50 ml) at 60° C. under nitrogen. Chromium trioxide(2 g) was added and the mixture stirred at 100° C. for 1/2 h, thencooled to r.t. The residue was poured into 1M KOH (500 ml) and extractedwith EtOAc (2×100 ml). The combined extracts were washed with brine,filtered (Whatman 1PS, phase separator) and evaporated. The product wascrystallised from EtOAc/hexanes as a pale green solid (1.72 g, 77%)andwas used without further purification.

¹ H NMR (270 MHz, CD₃ OD) δ 8.30 (1H, d, J=7 Hz); 8.0-7.7 (3H, m); 7.53(1H, br.s.); 7.24 (1H, br.s.) ppm.

7C 2-(2-Nitrobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)imidazole

The imidazole of example 7B (1.70 g, 7.83 mmol) was dissolved in dry DMF(15 ml) at 0° C. under nitrogen. Sodium hydride (260 mg, 80% disp. inoil, 8.6 mmol) was added portionwise with stirring and the mixturestirred at r.t. 1 h. 2-(trimethylsilyl)ethoxy!methyl chloride (1.5 g,8.6 mmol) and stirring continued at r.t. for 3 h. The mixture wasevaporated and partitioned between 5% KHCO₃ and EtOAc. The organicportion was washed with brine, evaporated and chromatographed on silicagel (eluant 45% EtOAc in hexanes) to provide the title compound as acolourless oil (1.51 g, 56%).

¹ H NMR (270 MHz, CDCl₃) δ 8.14 (1H, d, J=8 Hz); 7.8-7.6 (3H, m); 7.34(1H, s); 7.11 (1H, s); 5.97 (2H, s); 3.67 (2H, m); 0.96 (2H, m); 0.00(9H, s) ppm.

7D 2-(2-Aminobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)imidazole

The nitro-compound of example 7C (1.50 g, 4.32 mmol) was dissolved indry THF (60 ml) and the solution degassed and charged with 5%Pd.-on-carbon (800 mg). The mixture was hydrogenated on a Parr apparatusat 30 psi and r.t. for 2 h, then filtered (celite) and evaporated. Theresultant yellow oil was chromatographed on silica gel (eluant 40% EtOAcin hexanes) to provide the pure title compound (1.15 g, 84%).

¹ H NMR (270 MHz, CDCl₃) δ 8.38 (1H, d, J=8 Hz); 7.35 (3H, m); 6.77 (2H,m); 6.20 (2H, br.s.); 5.75 (2H, s); 3.60 (2H, m); 0.96 (2H, m); 0.00(9H, s) ppm.

7E(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(2-(1-((2-trimethylsilyl)ethoxy)methyl))imidazolyl)-1H-1,4-benzodiazepin-2-one

The amino ketone of example 7D (1.10 g, 3.47 mmol) was convened to thetitle compound by the method described in example 1C. The product wascrystallised from EtOAc/hexanes to provide a colourless solid (720 mg,41%).

¹ H NMR (270 MHz, CDCl₃) δ 9.63 (1H, br.s.); 7.6-7.2 (10H, m); 6.78 (1H,d, J=8 Hz); 6.67 (1H, d, J=8 Hz); 5.90 (1H, d, J=11 Hz); 5.63 (1H, d,J=11 Hz); 5.2 (3H, m); 3.60 (2H, m); 0.96 (2H, m); 0.00 (9H, s) ppm.

7F(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(2-(1-((2-(trimethylsilyl)ethoxy)methyl))imidazolyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 7E (505 mg, 1 mmol) was alkylated with1-bromopinacolone as described in example 1D. The product was purifiedby column chromatography on silica gel (eluant 75% EtOAc in hexanes) toprovide a pale yellow oil (420 mg, 70%).

¹ H NMR (270 MHz, CDCl₃) δ 7.63 (1H, dd, J₁ =8 Hz, J₂ =1.5 Hz); 7.52(1H, m); 7.4-7.3 (7H, m); 7.18 (1H, s); 7.07 (1H, d, J=8 Hz); 6.71 (1H,d, J=7.5 Hz); 5.91 (1H, d, J=10 Hz); 5.67 (1H, d, J=10 Hz); 5.43 (1H, d,J=7.5 Hz 5.15 (2H, s); 5.06 (1H, d, J=18 Hz); 4.36 (1H, d, J=18 Hz);3.60 (2H, m); 1.28 (9H, s); 0.95 (2H, m); 0.00 (9H, s) ppm.

7GN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-(1-((2-trimethylsilyl)ethoxy)methyl))imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The benzodiazepine of example 7F (95 mg, 0.157 mmol) was dissolved inethanol/acetic acid (95/5, v/v, 5 ml). The mixture was degassed and 5%Pd.-on-carbon (40 mg) added. The mixture was hydrogenated at atmosphericpressure and room temp. for 45 min, then filtered (celite filter aid),evaporated and azeotroped twice with toluene. The residue was taken upin DCM (2 ml) and m-tolyl isocyanate (24 μl, 0.19 mmol) added. Theresultant mixture was stirred at r.t. 1 h, then evaporated andchromatographed on silica gel (eluant 80% EtOAc in hexanes) to providethe title compound as a colourless solid (69 mg, 73%).

¹ H NMR (270 MHz, CDCl₃) δ 7.63 (1H, d, J=8 Hz); 7.55 (1H, t, J=8 Hz);7.4-7.0 (9H, m); 6.86 (1H, d, J=7.2 Hz); 5.97 (1H, d, J=10.5 Hz); 5.73(1H, d, J=10.5 Hz); 5.63 (1H, d, J=7.2 Hz); 4.94 (1H, d, J=18 Hz); 4.28(1H, d, J=18 Hz); 3.67 (2H, m); 2.31 (3H, s); 1.26 (9H, s); 0.96 (2H,m); 0.00 (9H, s) ppm.

7HN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The benzodiazepine of example 7G (69 mg, 0.1146 mmol) was taken up inethanol (8 ml) and conc. HCl (2 ml) added. The mixture was heated at 70°C. for 1 h and then cooled and evaporated. The residue was partitionedbetween 1M HCl and ether. The aqueous portion was basified and extractedwith EtOAc (×3). The combined extracts were filtered (Whatman 1PS, phaseseparator) and evaporated. The residue was chromatographed on silica gel(eluant EtOAc) and then further purified by MPLC on reverse-phase (C₁₈,eluting with a gradient of 20% MeCN in water to 100% MeCN) to provide acolourless solid (5 mg, 9%).

¹ H NMR (270 MHz, CDCl₃) δ 8.07 (1H, d, J=8 Hz); 7.6-6.9 (10H, m); 6.63(1H, d, J=7 Hz); 5.62 (1H, d, J=7 Hz); 5.41 (1H, d, J=17 Hz); 4.20 (1H,d, J=17 Hz); 2.18 (3H, s); 1.25 (9H, s).

EXAMPLE 8N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea##STR19## 8AN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-(1-((2-trimethylsilyl)ethoxy)methyl))imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea (Compound 6)

The benzodiazepine of example 7F (140 mg, 0.232 mmol) was taken up inethanol/acetic acid (95/5, v/v, 8 ml). The solution was degassed andthen charged with 5% Pd.-on-carbon (60 mg). The mixture was hydrogenatedat ambient temperature and pressure for 45 min, then filtered (celitefilter aid), evaporated and azeotroped with toluene (×2). The resultantamine was taken up in DCM and treated with an excess of3-(dimethylamino)phenyl isocyanate (prepared by refluxing a mixture of3-dimethylaminobenzoic acid (120 mg), triethylamine (147 μl) anddiphenylphosphoryl azide (280 mg) in benzene under N₂ for 3 h) at r.t. 4h. The mixture was evaporated and chromatographed on silica gel (eluant90% EtOAc in hexanes →EtOAc) to provide a colourless solid (106 mg,72%).

¹ H NMR (270 MHz, CDCl₃) δ 7.65 (1H, d, J=8 Hz); 7.54 (1H, t, J=8 Hz);7.36-7.23 (4H, m); 7.12-7.05 (3H, m); 6.91 (1H, m); 6.51-6.43 (2H, m);5.95 (1H, d, J=10.6 Hz); 5.76 (1H, d, J=10.6 Hz); 5.63 (1H, d, J=8 Hz);4.95 (1H, d, J=17.8 Hz); 4.22 (1H, d, J=17.8 Hz); 3.66 (2H, m); 2.95(6H, s); 1.26 (9H, s); 0.95 (2H, m); 0.00 (9H, s) ppm.

8BN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea

The benzodiazepine of example 8A (106 mg, 0.168 mmol) was dissolved indry DCM (20 ml) and the solution cooled to 0° C. Dry HBr gas was bubbledslowly through the mixture at 0° C. for 1/2 h. The mixture was stopperedand sitting continued for a further 1/2 h at 0° C.

The mixture was then degassed and evaporated. The residue waspartitioned between 1M KOH and EtOAc. The organic portion was washedwith brine, filtered (Whatman 1PS, phase separator) and evaporated. Theproduct was chromatographed on silica gel (eluant 2% MeOH in EtOAc) andthe title compound isolated as a colourless solid by freeze drying fromacetonitrile-water (48 mg, 60%).

¹ H NMR (270 MHz, CDCl₃) δ 8.11 (1H, d, J=8 Hz); 7.62 (1H, t, J=8 Hz);7.48-7.31 (3H, m); 7.05-6.93 (4H, m); 6.70 (1H, br.s.); 6.32 (1H, d, J=8Hz); 6.27 (1H, br.d.); 5.73 (1H, d, J=7.4 Hz); 5.40 (1H, d, J=17.5 Hz);4.48 (1H, d, J=17.5 Hz); 2.89 (6H, s); 1.16 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =502.3

EXAMPLE 9N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrrolidyl)phenyl)urea(Compound 19) ##STR20## 9A 3-(1-Pyrrolidyl)benzoic acid

m-Amino benzoic acid (13.7 g, 0.1 mol) was taken up in methanol (150 ml)and cooled to 0° C. Acetyl chloride (10 ml) was added dropwise, and thenthe mixture heated until reflux, under nitrogen for 14 h. The mixturewas cooled, evaporated and partitioned between EtOAc and 5% KHCO₃. Theorganic portion was washed with brine, filtered (Whatman 1PS, phaseseparator) and evaporated to provide a brown oil which crystallised onstanding (13.2 g, 88%). A portion of the amino ester (5.45 g, 36.1 mmol)was taken up in dry DMP (70 ml) and treated with sodium hydride (3.78 g,80% disp. in oil, 126 mmol) at 0° C. under nitrogen for 11/2 h.1,4-dibromobutane (14.05 g, 65 mmol) and potassium iodide (0.6 g, 3.7mmol) were added and the mixture heated at 80° C. for 72 h. The mixturewas cooled, evaporated and partitioned between EtOAc and 5% KHCO₃. Theorganic portion was washed with brine, filtered (Whatman 1PS, phaseseparator) and evaporated. The residue was chromatographed on silica(eluant 8% EtOAc/hexane) to provide a pale yellow solid (1.70 g, 23%).The solid was taken up in dioxan/water (40 ml) and treated with LiOH.7H₂O (1.75 g, 5 eq) at r.t. for 10 min, then at 40° C. for 30 min. Aceticacid (10 was added and the mixture was evaporated, azeotroped withtoluene and crystallised from AcOH/water/dioxan to provide a pale brownsolid (1.26 g, 80%) which was dried in vacuo over P₂ O₅.

¹ H NMR (270 MHz, CDCl₃) δ 7.4-7.2 (3H, m); 6.78 (1H, m); 3.35 (4H, m);2.02 (4H, m) ppm.

9N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-(1-((2-trimethylsilyl)ethoxy)methyl))imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrrolidyl)phenyl)urea

The benzodiazepine of example 7F (140 mg, 0.232) was taken up inethanol/acetic acid (95/5, v/v, 8 ml) and hydrogenated over 5%Pck-on-carbon (60 mg) at ambient pressure and temperature for 45 min.The mixture was filtered (celite, filter aid), evaporated and azeotropedwith toluene (×2). The residue was taken up in DCM (4 ml) and treatedwith 3-(1-pyrrolidyl)phenyl isocyanate (prepared by refluxing a mixtureof the acid of example 9A (140 mg), triethylamine (147 μl) anddiphenylphosphoryl azide (280 mg) in benzene (10 ml) for 2 h) at r.t. 4h. The mixture was evaporated and chromatographed on silica gel (eluant90% EtOAc in hexanes→EtOAc) to provide a colourless solid (110 mg, 72%).

¹ H NMR (270 MHz, CDCl₃) δ 7.65 (1H, dd, J₁ =8 Hz, J₂ =1.7 Hz); 7.54(1H, dt. J_(t) 8 Hz, J_(d) =1.8 Hz); 7.4-7.0 (7H, m); 6.75 (1H, m); 6.43(1H, d J=8 Hz); 6.31 (1H, d, J=8 Hz); 5.95 (1H, d, J=10.4 Hz); 5.75 (1H,d, J=10.4 Hz); 5.63 (1H, d, J=7.2 Hz); 4.96 (1H, d, J=17.8 Hz); 4.26(1H, d, J=17.8 Hz); 3.63 (2H, m); 3.29 (4H, m); 2.00 (4H, m); 1.27 (9H,s); 0.95 (2H, m); 0.00 (9H, s) ppm.

9CN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(2-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-pyrrolidyl)phenyl)urea

The benzodiazepine of example 9B (110 mg, 0.1674 mmol) was deprotectedwith HBr as described in example 8B. The product was chromatographed onsilica gel (eluant 2% MeOH in EtOAc) and freeze-dried fromacetonitrile-water to provide a pale yellow solid (46 mg, 55%).

¹ H NMR (270 Hz, CDCl₃) δ 8.11 (1H, d, J =7 Hz); 7.62 (1H, t, J=7 Hz);7.47-7.2 (4H, m); 7.09-6.80 (4H, m); 6.23-6.13 (2H, m); 5.74 (1H, d,J=7.2 Hz); 5.36 (1H, d, J=17.5 Hz); 4.49 (1H, d, J=17.5 Hz); 3.21 (4H,m); 1.95 (4H m); 1.16 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =528.8.

EXAMPLE 10N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-5-(4-imidazolyl)-2-oxo-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Compound 12) ##STR21## 10A5-(Hydroxy(2-nitrophenyl))methyl-N,N-dimethylimidazole-1-sulphonamide

N,N-Dimethylimidazole-1-sulphonamide (Chadwick and Ngochindo, J Chem SocPerkin Trans I 1984, 481) (6.0 g, 34.8 mmol) was taken up in dry THF(150 ml) at -78° C. under nitrogen. n-Butyl lithium (24 ml, 1.6Msolution in hexanes) was added dropwise and stirring continued at -78°C. for 1/2 h. Triethylchlorosilane (11.7 ml, 69.6 mmol) was then addedand the mixture allowed to warm to r.t. and stirred overnight. Themixture was then evaporated at below 50° C. under high vacuum to removeall volatiles. The residue was redissolved in dry THF (100 ml) at -78°C. under nitrogen and treated dropwise with sec-butyl lithium (53 ml,1.3M solution in cyclohexane). The mixture was stirred at -78° C. for 45min, then a solution of o-nitrobenzaldehyde (10.5 g) added in the THF(40 ml). The mixture was allowed to warm to r.t. and stirred 22 h. Themixture was then evaporated and partitioned between 2M HCl (100 ml) andether (150 ml). The aqueous portion was basified and extracted withEtOAc (×2). The combined extracts were filtered (Whatman 1PS, phaseseparator) and evaporated and the product crystallised from EtOAc/hexaneto provide a pale yellow solid (3.86 g, 34%).

¹ H NMR (270 MHz, CDCl₃) δ 8.13 (1H, d, J=8 Hz); 8.12 (1H, d, J=8 Hz);7.92 (1H, d, J=1 Hz); 7.79 (1H, t, J=8 Hz); 7.57 (1H, t, J=8 Hz); 6.70(1H, s 6.28 (1H, s); 3.08 (6H, s) ppm.

10B 4-(2-nitrobenzoyl)imidazole

The imidazole of example 10A (3.8 g, 11.66 mmol) was taken up in aceticacid (60 ml) at 40° C. Chromium trioxide (2.3 g) was added and themixture heated at 100° C. for 1 h, then cooled and poured intoice-water. The mixture was basified and extracted with EtOAc (×3). Thecombined extracts were evaporated, azeotroped with toluene and theresidue crystallised from EtOAc/hexane to provide an off-white solid(725 mg, 29%).

¹ H NMR (270 MHz, CDCl₃) δ 7.81 (1H, d, J=7 Hz); 7.5-7.3 (5H, m); 3.25(6H, s) ppm.

10C 4-(2-Nitrobenzoyl)-1-((2-trimethylsilyl)ethoxy)methyl)imidazole and

10D 5-(2-Nitrobenzoyl)-1-((2-trimethylsilyl)ethoxy)methyl)imidazole

The imidazole of example 10B (700 mg, 3.226 mmol) was dissolved in dryDMF (15 ml) at 0° C. under nitrogen. Sodium hydride (106 mg, 80% disp.in oil) was added portionwise and the mixture stirred at 0° C.→r.t. over1 h. 2-(Trimethylsilyl)ethoxy!methyl chloride (620 mg, 3.55 mmol) wasadded and stirring continued at r.t. 1 h. The mixture was then pouredinto 5% KHCO₃ and extracted with EtOAc. The extracts were washed withbrine, filtered (Whatman 1PS, phase separator) and evaporated. Theresidue was chromatographed on silica gel (eluant 80% EtOAc in hexanesuntil removal of fast product then EtOAc) to provide two colourlessoils. 10C was obtained in 29% yield (320 mg), the faster eluting isomerand 10D was obtained in 31% yield (350 mg), the slower eluting isomer.

10C ¹ H NMR (270 MHz, CDCl₃) δ 8.15 (1H, d, J=7.5 Hz); 7.86 (1H, s);7.78-7.58 (3H m); 7.53 (1H, s); 5.31 (2H, s); 3.52 (2H, m); 0.92 (2H,m); 0.00 (9H, s) ppm.

10D ¹ H NMR (270 MHz, CDCl₃) δ 8.17 (1H, d, J=7.5 Hz); 7.91 (1H, s);7.79-7.64 (2H, m); 7.53 (1H, dd, J₁ =7.5 Hz, J₂ =1.5 Hz); 7.18 (1H, s);5.85 (2H, s); 3.70 (2H, m); 0.97 (2H, m); 0.00(9H, s) ppm.

10E 4-(2-Aminobenzoyly)-1-((2-trimethylsilyl)ethoxy)-imidazole

The imidazole of example 10C (320 mg, 0.922 mmol) was dissolved in dryTHF (25 ml) and hydrogenated over 5% Pd.-on-carbon at 25 psi and r.t.for 2 h. The mixture was filtered (celite filter aid) and evaporated toprovide a yellow oil (286 mg, 98%) which was used in the next reactionwithout further purification.

¹ H NMR (270 MHz, CDCl₃) δ 8.42 (1H, dd., J₁ =8.2 Hz, J₂ =1.6 Hz); 7.69(2H, m); 7.27 (1H, m); 6.70 (2H, m); 6.03 (2H, br.s.); 5.32 (2H, s);3.54 (2H, m); 0.95 (2H, m); 0.00 (9H, s) ppm.

10F(3RS)-Benzyloxycarbonylamino-2,3-dihydro-5-(4-(1-((2-trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-2-one

The imidazole of example 10E (286 mg, 0.902 mmol) was converted to thebenzodiazepine title compound by the method described in example 1C. Theproduct was chromatographed on silica gel (eluant 3% MeOH in EtOAc) toprovide a pale yellow oil (300 mg, 66%).

¹ H NMR (270 MHz, CDCl₃) δ 9.75 (1H, s); 7.66-7.13 (10H, m); 6.96 (1H,d, J=8 Hz); 6.62 (1H, d, J=8 Hz); 5.38-5.07 (5H, m); 3.52 (2H, t, J=8Hz); 0.92 (2H, t, J=8 Hz); 0.130 (9H, s) ppm.

10G (3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(4-(1-((2-(trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 10F (300 mg, 0.594 mmol) was alkylatedwith 1-bromopinacolone as described in example 1D. The product waschromatographed (eluant 2% MeOH in EtOAc) to provide a colourless foam(305 mg, 85%).

¹ H NMR (270 MHz, CDC₃) δ 7.68 (1H, d, J=7.6 Hz); 7.60 (1H, s); 7.49(1H, t, J=7.6 Hz); 7.35-7.22 (6H, m); 7.05 (1H, d, J=8 Hz); 6.63 (1H, d,J=8 Hz); 5.46 (1H, d, J=8 Hz); 5.27 (2H, s); 5.10 (2H, m); 5.03 (1H, d,J=17.8 Hz); 4.38 (1H, d J=17.8 Hz); 3.51 (2H, t, J=8 Hz); 1.24 (9H, s);0.92 (2H, t, J=8 Hz) 0.00 (9H, s) ppm.

10HN-3((RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-4-(1-((2(trimethylsilyl)ethoxy)methyl))-imidazol-1-H-1,4-benzodiazepin-3yl)-N'-(3-methylphenyl)urea

The title compound was prepared from the benzodiazepine of example 10G(150 mg, 0.249 mmol) by the method described in example 7G. The productwas chromatographed on silica gel (eluant EtOAc→5% MeOH in EtOAc) toprovide a colourless solid (97 mg, 65%).

¹ H NMR (270 MHz, CDCl₃) δ 7.77 (1H, s); 7.71 (1H, d, J=8 Hz); 7.62 (1H,s); 7.51 (1H, t, J=7 Hz); 7.33-6.93 (7H, m); 6.77 (1H, d, J=7 Hz); 5.70(1H, d, J=8.2 Hz); 5.21 (2H, s); 4.87 (1H, d, J=17.8 Hz); 4.41 (1H, d,J=17.8 Hz); 3.51 (2H, t, J=7.5 Hz); 2.24 (3H, s); 1.20 (9H, s); 0.91(2H, t, J=7.5 Hz); 0.00 (9H, s).

10IN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The title compound was prepared by treatment of the benzodiazepine ofexample 10H with HBr as described in example 8B, and the productcrystallised from DCM/hexane to provide a white solid (44 mg, 58%).

¹ HNMR (270 MHz, CDCl₃) δ 7.69 (1H, d, J=7 Hz); 7.56-7.19 (8H, m);6.91-6.85 (3H, m); 6.86 (1H, d, J=7 Hz); 5.53 (1H, d, J=7 Hz); 5.22 (1H,br. d.); 4.41 (1H, d, J=17.5 Hz); 2.07 (3H, s); 1.06 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =473.3.

EXAMPLE 11N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(Compound 8) ##STR22## 11AN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-(1-((2-trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea

The title compound was prepared from the benzodiazepine of example 10G(150 mg, 0.249 mmol) by the method described in example 8A. The productwas chromatographed on silica gel (eluant EtOAc→5% MeOH in EtOAc) toprovide a colourless solid (130 mg, 83%).

¹ H NMR (270 MHz, CDCl₃) δ 7.78 (1H, s); 7.71 (1H, d, J=8 Hz); 7.65 (1H,s); 7.50 (1H, t, J=7 Hz); 7.38-7.25 (3H, m); 7.06-6.96 (2H, m); 6.89(1H, s); 6.42-6.32 (2H, m); 5.70 (1H, d, J=8 Hz); 5.22 (2H, s); 4.85(1H, d, J=17.8 Hz); 4.26 (1H, d, J=17.8 Hz); 3.51 (2H, t, J=8 Hz); 2.86(6H, s); 1.20 (9H, s); 0.91 (2H, t, J=8 Hz); 0.00 (9H, s) ppm.

11BN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea

The title compound was prepared from the benzodiazepine of example 11Aas described in example 8B. The product was crystallised fromEtOAc/hexane to provide an off-white solid (69 mg, 70%).

¹ H NMR (270 MHz, CDCl₃) δ 7.87 (1H, d, J=7.8 Hz); 7.71-7.03 (10H, m);6.48-6.39 (2H, m); 5.71 (1H, d, J=7 Hz); 5.22 (1H, br.d.); 4.66 (1H, d,J=17.6 Hz); 2.92 (6H, s); 1.25 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =502.3.

EXAMPLE 12N-((3RS)-1-(4-methylphenyl)carbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Compound 20) ##STR23## 12A5-(2-Aminobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-imidazole

The imidazole of example 10D (350 mg, 1.009 mmol) was hydrogenated over5% Pd.-on-carbon as described in example 10E. The yellow oil product(313 mg, 98%) was used in the next reaction without furtherpurification.

¹ H NMR (270 MHz, CDCl₃) δ 7.89 (1H, s); 7.81 (1H, dd, J₁ =8 Hz, J₂ =1.6Hz); 7.53 (1H, s); 7.34 (1H, dr, J_(t) =8 Hz, J_(d) =1.6 Hz); 6.77-6.68(2H, m); br.s.); 5.77 (2H, s); 3.62 (2H, m); 0.96 (2H, m); 0.00 (9H, s).

12B(3RS)-3-Benzyloxycarbonylamino-2,3-dihydro-5-(5-(1-((2-(trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-2-one

The imidazole of example 12A (313 mg, 0.98 mmol) was converted to thebenzodiazepine title compound by the method described in example 1C. Theproduct was purified by chromatography (eluant 2% MeOH in EtOAc) toprovide a yellow oil (204 mg, 41%).

¹ H NMR (270 MHz, CDCl₃) δ 9.89 (1H, s); 8.58 (1H, d, J=8 Hz); 7.94-7.0(10H, m); 6.67 (1H, d, J=8 Hz); 5.92 (1H, d, J=10.5 Hz); 5.59 (1H, d,J=10.5 Hz); 5.29 (1H, d, J=8 Hz); 5.17 (2H, s); 3.63 (2H, t, J=8 Hz);0.93 (2H, t, J=8 Hz); 0.00 (9H, s) ppm.

12C(3RS)-3-Benzyloxycarbonylamino-1-((4-methylphenyl)carbonylmethyl)-2,3-dihydro-5-(5-(1-((2-trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of example 12C (60 mg, 0.118 mmol) was dissolved inDMF (5 ml) at 0° C. under N₂. Sodium hydride (15 mg, 80% disp. in oil)was added and the mixture stirred at r.t. 40 min.2-Bromo-(4'-methyl)acetophenone (110 mg, 0.515 mmol) was then added andstirring continued at r.t. 2 h. The mixture was evaporated andpartitioned between EtOAc and brine. The organic portion was filtered(Whatman 1PS phase separator) and evaporated and the productchromatographed on silica gel (eluant 90% EtOAc in hexanes→EtOAc) toprovide the tide compound as a pale yellow oil (35 mg, 48%).

¹ H NMR (270 MHz, CDCl₃) δ 7.85-7.80 (3H, m); 7.63 (1H, d, J=7.5 Hz);7.55 (1H, t, J=7.5 Hz); 7.37-7.23 (8H, m); 6.99 (1H, s); 6.63 (1H, d,J=8 Hz); 5.92 (1H, d, J=10 Hz); 5.61 (1H, d, J=10 Hz); 5.45 (1H, d, J=8Hz); 5.37 (1H, d, J=17.5 Hz); 5.19-5.13 (3H, m); 3.63 (2H, m); 2.40 (3H,s); 0.93 (2H, m); 0.00 (9H, s) ppm.

12DN-((3RS)-1-(4-methylphenyl)carbonylmethyl-2,3-dihydro-2-oxo-5-(5-(1-((2-(trimethylsilyl)ethoxy)methyl))-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The benzodiazepine of example 12C (35 mg, 0.055 mmol) was converted tothe 3-methylphenyl urea as described in example 7G. The product waschromatographed on silica gel (eluant 95% EtOAc in hexanes) to provide acolourless oH (30 mg, 86%).

¹ H NMR (270 MHz, CDCl₃) δ 7.88-7.73 (3H, m); 7.13 (1H, d, J=8 Hz); 7.58(1H, t, J=8 Hz); 7.39-7.11 (7H, m); 6.97 (1H, d, J=7 Hz); 6.90 (1H, d,J=7 Hz); 6.68-6.57 (2H, m); 6.00 (1H, d, J=10 Hz); 5.72 (1H, d, J=7 Hz);5.57 (1H, d, J=10 Hz); 5.34 (2H, s); 3.65 (2H, m); 2.47 (3H, s); 2.35(3H, s); 0.92 (2H, m); 0.00 (9H, s) ppm.

12EN-((3RS)-1-(4-methylphenyl)carbonylmethyl-2,3-dihydro-2-oxo-5-(4-imidazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The benzodiazepine of example 12D (30 mg, 0.047 mmol) was treated withHBr gas as described in example 8B. The product was purified by MPLC onreverse-phase (C₁₈, eluting with a gradient of 20% MeCN in water to 100%MeCN) to provide a colourless solid when freeze dried (10 mg, 42%).

¹ H NMR (270 MHz, CDCl₃) δ 7.70-6.40 (17H, m); 5.76 (1H, d, J=17 Hz);5.64 (1H, d, J=8 Hz); 5.01 (1H, d, J=17 Hz); 2.26 (3H, s); 2.10 (3H, s)ppm.

EXAMPLE 13N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea(Compound 9) ##STR24## 13A 3-(Hydroxy-(2-nitrophenyl))methyl pyrazole

1-(1-Pyrrolidino)methyl pyrazole (Katritsky et at., J Org Chem 1988, 53,5685; 5.54 g, 36.7 mmol) was taken up in dry ether (120 ml) at -70° C.under N₂, and treated dropwise with n-butyl lithium (25.2 ml, 1.6Msolution in hexanes). The mixture was stirred at -70° C. for 11/2 h andthen a solution of o-nitrobenzaldehyde (6.1 g, 40.4 mmol) added in dryTHF (25 ml). The mixture was allowed to warm to r.t. over 1/2 h and thenstirred for a further 2 h. 2M HCl (100 ml) was then added and stirringcontinued at r.t. 10 min. The two phases were separated and the aqueousportion neutralised with conc. ammonia and extracted with CHCl₃ (×2).The extracts were dried (MgSO₄), evaporated and chromatographed onsilica gel (eluant 40% EtOAc in hexanes) to provide the title compoundas a pale brown oil (2.51 g, 31%).

13B 3-(2-Nitrobenzoyl)-pyrazole

The pyrazole of example 13A (2.5g, 11.4 mmol) was oxidised with CrO₃ bythe method described in example 7B. The product was crystallised fromDCM-hexane to provide an off-white solid (1.78 g, 72%).

¹ H NMR (270 MHz, CDCl₃) δ 13.5 (1H, br.s.); 8.18 (1H, d, J=8 Hz);7.95-7.7 (4H, m); 6.94 (1H, s) ppm.

13C 3-(2-nitrobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-pyrazole and

13D 5-(2-nitrobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-pyrazole

The pyrazole of example 13B (1.70 g, 7.835 mmol) was added in smallportions to a stirring mixture of NaH (260 mg, 80% disp. in oil-hexanewashed) in dry DMF (20 ml) at r.t. under nitrogen. The mixture wasstirred at r.t. 2 h, then ((2-(trimethylsilyl)ethoxy) methyl)-chloride(1.5 g, 8.6 mmol) added dropwise. Stirring was continued for a further 2h at r.t. and then the mixture poured into water (200 ml) and extractedwith EtOAc (x 2). The extracts were filtered (Whatman 1PS phaseseparator), evaporated and chromatographed on silica gel (eluant 30%EtOAc in hexanes) to provide the two title compounds as a 1:1 mixture(2.35 g, 86%).

¹ H NMR (270 MHz, CDCl₃) δ 8.24 (0.5H, d, J=8 Hz); 8.16 (0.5H, d, J=8Hz); 7.8-7.5 (4H, m); 7.08 (0.5H, d, J=1 Hz); 6.33 (0.5H, d, J=1 Hz);6.00 (1H, s); 5.39 (1H, s); 3.77 (1H, m); 3.46 (1H, m); 1.02 (1H, m);0.92 (1H, m); 0.04 (4.5H, s); 0.00 (4.5H, s) ppm.

13E 3-(2-Aminobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-pyrazole and

13F 5-(2-Aminobenzoyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-pyrazole

The mixture of pyrazoles of examples 13C and 13D (2.35 g, 6.772 mmol)was taken up in dry THF (100 ml) and degassed. 5% Pd.-on-carbon (1.2 g)was added and the mixture hydrogenated at 30 psi and ambient temperaturefor 2 h. The mixture was filtered (celite filter aid) and evaporated andthen chromatographed (eluant 30% EtOAc in hexanes) to provide the twotide compounds as an equimolar mixture (1.05 g, 49%).

¹ H NMR (270 MHz, CDCl₃) δ 8.43 (0.5H, dd, J₁ =8 Hz, J₂ =1.5 Hz);7.76-7.65 (1.5H, m); 7.39 (1H, m); 6.98 (0.5H, d, J=2.3 Hz); 6.81-6.63(2.5H, m); 6.26 (2H, br.s.); 5.85 (1H, s); 5.60 (1H, s); 3.75-3.60 (2H,m); 1.02-0.90 (2H, m); 0.08 (4.5H, s); 0.00 (4.5H, s) ppm.

13G(3RS)-3-Benzyloxycarbonylamino-2,3-dihydro-5-(3-(1-((2-(trimethylsilyl)ethoxy)methyl))-pyrazolyl)-1H-1,4-benzodiazepin-2-one and

13H(3RS)-3-Benzyloxycarbonylamino-2,3-dihydro-5-(5-(1-((2-(trimethylsilyl)ethoxy)methyl))-pyrazolyl)-1H-1,4-benzodiazepin-2-one

The mixture of pyrazoles, examples 13E and 13F, (1.0 g, 3.155 mmol) wereconverted to the benzodiazepine title compounds by the method describedin example 1C. The product was purified by chromatography on silica gel(eluant 55% EtOAc in hexanes) to provide an equimolar mixture of thetitle compounds (1.21 g, 76%).

¹ H NMR (270 MHz, CDCl₃) δ 8.64 (1H, m); 8.32 (1H, br.s.); 7.8-7.05 (9H,m); 6.96 (0.5H, d, J=1.4 Hz); 6.62 (1H, m); 6.41 (0.5H, br.s.); 5.96(1H, s); 5.52-5.46 (1.54, m); 5.21 (2H, s); 5.09 (0.5H, br.s.); 3.56(2H, m); 0.96 (2H, m); 0.09 (4.5H, s); 0.00 (4.5H, s) ppm.

13I(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(3-(1-((2-(trimethylsilyl)ethoxy)methyl))pyrazolyl)-1H-1,4-benzodiazepin-2-oneand

13J(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(5-(1-((2-(trimethylsilyl)ethoxy)methyl))pyrazolyl)-1H-1,4-benzodiazepin-2-one

The 1:1 mixture of benzodiazepines of examples 13G and 13H (1.10 g,2.178 mmol) was alkylated with 1-bromopinacolone by the method describedin. example 1D. The product was chromatographed (eluant 45% EtOAc inhexanes) to provide the title compounds as a equimolar mixture (860 mg,66%).

¹ H NMR (270 MHz, CDCl₃) δ 7.71 (1H, d, J=8 Hz); 7.6-7.0 (9H, m); 6.90(1H, d, J=1.7 Hz); 6.67 (1H, d, J=8 Hz); 5.50 (1H, d, J=8 Hz); 5.43 (2H,m); 5.12 (2H, s); 5.02 (1H, d, J=17.5 Hz); 4.37 (1H, d, J=17.5 Hz); 3.59(2H, m); 1.26 (9H, s); 0.94 (2H, m); 0.01 (4.51H, s); 0.00 (4.5H, s)ppm.

13K(3RS)-Amino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-2-one

The mixture of benzodiazepines of examples 13I and 13J (350 mg, 0.58mmol) was taken up in DCM (10 ml) and cooled to 0° C. Dry HBr gas wasslowly bubbled through the mixture with stirring for 25 min. The mixturewas then stoppered and stirred for a further 2 h at 0° C. The mixturewas evaporated, taken up in 1M HCl and washed with ether. The aqueousportion was basified and extracted with CHCl₃ (x3). The combinedextracts were washed with brine, filtered (Whatman 1PS phase separator)and evaporated. The residue was pure enough to be used in the next stepwithout further purification (140 mg, 71%).

¹ H NMR (270 MHz, CDCl₃) δ 7.67 (1H, dd, J₁ =8 Hz, J₂ =1.5 Hz); 7.60(1H, d, J=2 Hz); 7.32-7.24 (2H, m); 7.09 (1H, d, J=8 Hz); 6.50 (1H, d,J=2 Hz); 5.09 (1H, d, J=17.5 Hz); 4.64 (1H, s); 4.41 (1H, d, J=17.5 Hz);1.27 (9H, s) ppm.

13LN-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyrazolyl)-1H-1,4-benzodiazepin-3-yl-N'-(3-methylphenyl)urea

The benzodiazepine of example 13K (70 mg, 0.2065 mmol) was taken up inDCM (2 ml) and m-tolyl isocyanate (32 μl) added. The mixture was stirredat r.t. 2 h, then evaporated and chromatographed on silica gel (eluant80% EtOAc in hexanes) to provide the title compound which wasfreeze-dried from acetonitrile-water (22 mg, 23%).

¹ H NMR (270 MHz, CDCl₃) δ 7.57`7.51 (3H, m); 7.35-7.02 (11H, m); 6.76(1H, m); 6.38 (1H, d, J=2 Hz); 5.67 (1H, d, J=8 Hz); 4.8 (2H, m); 2.21(3H, s); 1.19 (9H, s) ppm.

M.S. (+ve FAB) M+H!⁺ =473.2

Compounds 10-16 of List A are obtainable by methods analogous to thosedescribed in the above examples.

EXAMPLE 14 Etoc-(1-benzotriazolyl)glycine

The title compound was prepared according to the method of Katritsky (JOrg Chem 1990, 55, 2266). Ethyl carbamate (1.80 g, 20 mmol), glyoxylicacid hydrate (1.84 g, 20 mmol) and benzotriazole (2.38 g, 20 mmol) wereheated under reflux together in benzene (60 ml) under Dean-Starkconditions for 2 h. The mixture was allowed to cool, diluted with ether(120 ml) and filtered to provide the tide compound as a colourless solid(3.73 g, 85%).

¹ H NMR (270 MHz, CD₃ OD) δ 7.6.5 (1H, d, J=8 Hz); 7.55 (1H, d, J=8 Hz);7.22 (1H, t, J=8 Hz); 7.09 (1H, t, J=8 Hz); 6.83 (1H, s); 3.67 (2H, m);0.84 (3H, m) ppm.

EXAMPLE 15 2-(2-Aminobenzoyl)pyridine

2-Bromopyridine-(13.11 g, 83.0 mmol) was dissolved in toluene (50 mL)under nitrogen. ^(n) BuLi (1.6M solution in ^(n) hexane; 50 mL, 80.0mmol) was added dropwise to the solution below -60° C. After stirringwas continued for a further 15 min at this temperature, a solution ofanthranilonitrile (4.25 g, 35.0 mmol) in toluene (25 mL) was addeddropwise to the solution over 8 min. below -60° C. After addition wascomplete, the mixture was stirred at -60° C. for 15 min. and thenallowed to warm to 5° C. After stirring for an additional 2 h at 5° C.,the mixture was poured into ice-cold 3N HCl (80 mL) and stirred at roomtemperature for 1 h. The separated organic portion was extracted with 1NHCl (40 mL). The combined aqueous portions were washed with toluene (20mL) and basified to pH 9 with 25% aqueous ammonia at 0°-°5° C. Stirringwas continued for a further 1 h at this temperature, and the resultantprecipitate was collected by filtration, washed with water and dried toafford a crude solid (7.09 g). Recrystallisation from isopropanolprovided crystalline product (I) (6.10 g, 86%).

EXAMPLE 16(3RS)-(Ethoxycarbonyl)amino-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

2-(2-Aminobenzoyl)pyridine (1.39 g, 7 mmol) and Etoc-(1-benzotriazolyl)glycine (2.47 g, 11.2 mmol) were combined in DCM (25 nil) at 0° C. DMAP(100 mg) was added followed by water soluble carbodiimide (1.95 g, 10mmol). The ice-bath was removed and stirring continued for 30 min. Themixture was evaporated and partitioned between EtOAc and 5% NaHCO₃. Theorganic portion was washed with brine, dried and evaporated. The productwas taken up in ice-cold saturated ammonia in methanol (60 ml),stoppered and stirred at r.t. 1 h. The mixture was concentrated andtaken up in acetic acid (80 ml) and stirred at r.t. 4 h. The mixture wasconcentrated and partitioned between CHCl₃ and 1M KOH. The organicportion was washed with brine, dried and concentrated and the productcrystallised from EtOAc/hexane as a white solid (1.25 g, 55%).

¹ H NMR (270 MHz, CHCl₃) δ 8.69 (1H, s); 8.62 (1H, d, J=1.5 Hz); 8.10(1H, d, J=8 Hz); 7.83 (1H, dt, J_(t) =8 Hz, J_(d) =1.5 Hz); 7.50-7.17(4H, m); 7.00 (1H, d, J=8.2 Hz); 5.36 (1H, d, J=8.2 Hz); 4.17 (2H, q,J=7 Hz); 1.29 (3H, t, J=7 Hz) ppm.

EXAMPLE 17(3RS)-Ethyloxycarbonylamino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(3RS)-Ethyloxycarbonylamino-1,3-dihydro-5-(2-pyridyl)-2H-1,4-benzodiazepin-2-one(1.1 g, 3.395 mmol) was azeotroped with DMF then taken up in dry DMF (25ml) at 0° C. under nitrogen. Sodium hydride (142 mg, 4.75 mmol) wasadded and the mixture allowed to warm to r.t. over 45 min. withstirring. 1-Bromopinacolone (760 mg, 4.25 mmol) was then added andstirring continued at r.t. for 45 min. The mixture was then quenchedwith water and evaporated. The residue was partitioned between CHCl₃ andbrine and the organic portion dried and evaporated. The product wascrystallised from EtOAc/hexane to provide an off-white solid (1.22 g,85%).

¹ H NMR (270 1 MHz, CDCl₃) δ 8.60 (1H, d, J=4 Hz); 8.15 (1H, d, J=8 Hz);7.80 (1H, dt, J_(t) =8 Hz, J_(d) =1.6 Hz); 7.52 (1H, t, J=7 Hz);7.40-7.20 (3H, m); 7.11 (1H, d, 8.2 Hz); 6.60 (1H, d, J=8.2 Hz); 5.49(1H, d, J=8.2 Hz); 5.03 (1H, d, J=17.5 Hz); 4.48 (1H, d, J=17.5 Hz);4.15 (2H, q, J=7 Hz); 1.29-1.24 (12H, m) ppm.

EXAMPLE 18(3RS)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(3RS)-Ethyloxycarbonylamino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one(IV, 250 mg, 0.592 mmol) was taken up in dry DCM (10 ml) at 0° C. andsaturated with dry HBr gas. The mixture was stoppered and stirred atr.t. for 64 h. The solvent was evaporated and the product partitionedbetween 1M HCl and EtOAc. The acid portion was basified and extractedwith CHCl₃ (×3). The extracts were combined and washed with brine, driedand evaporated to give a brown foam (188 mg, 91%), which was notpurified further.

¹ H NMR (CDCl₃, 270 MHz) δ 8.58 (1H, m); 8.08 (1H, d, J=8 Hz); 7.72 (1H,t, J=8 Hz); 7.41 (1H, t, J=8 Hz); 7.3-7.0 (5H, m); 5.00 (1H, d, J=17Hz); 4.60 (1H, s); 4.38 (1H, d, J=17 Hz); 2.2 (2H, br.s); 1.22 (9H, s)ppm.

EXAMPLES 19 and 20 (3R) and(3S)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(3RS)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepine-2-one(2.2 g, 6.28 mmol) was taken up in MeCN (8 ml) at -5° C. (R)-mandelicacid (440 mg, 3.14 mmol) was added and the mixture stirred at -5° C. andseeded. As a thick precipitate began to form MeCN (8 ml) was addeddropwise to enable easier filtration. After 1 hr at -5° C. the mixturewas filtered and washed with small portions of cold MeCN. The resultantwhite precipitate (0.92 g, 30%) was recrystallised from MeCN. The saltwas washed with base to give the free (R)-amine α!_(D) =+212.6°(c=0.715, CHCl₃).

The filtrate from above was washed with base and taken up in MeCN (6ml). Addition of (S)-mandelic acid afforded the (S)-amine salt in thesame manner (0.85 g, 28%). This was recrystallised from MeCN and washedwith base to provide the free (S)-amine α!_(D) =-213.4° (c=0.671,CHCl₃).

The ¹ H NMR of each amine was identical to that for the (R,S)-mixture.

EXAMPLE 21 3-(Dimethylamino)phenyl isocyanate

3-(Dimethylamino)benzoic acid (350 g, 2.12 mol) was dissolved in acetone(2.8 L). Et₃ N (249 g, 2.46 tool) was added dropwise to the solutionbelow 10° C., followed by the addition of a solution of ethylchloroformate (287 g, 2.65 mol) in acetone (875 mL) below 5° C. Afterstirring for 30 min, a solution of NaN₃ (201 g, 3.18 mol) in water (570ml) was added dropwise below 5° C. The reaction mixture was stirred at0°-5° C. for a further 1 h, then poured into toluene-ice water (2:3, 11L). The aqueous portion was extracted with a small amount of toluene andthe combined organic portions were washed with water and brine and dried(MgSO₄). After removing MgSO₄ by filtration, the filtrate was addeddropwise to hot toluene (1.5 L). The mixture was refluxed for 1 h andthen evaporated under reduced pressure. The residue was distilled(0.6-0.8 mmHg, 74°-77° C.) to afford the pure isocyanate (252 g, 74%) asa yellow oil.

EXAMPLE 22N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-((3-dimethylamino)phenyl)urea

The (R)-amine of Example 19 (410 mg, 1.17 mmol) in DCM (5 ml) wastreated with the isocyanate of Example 8 (1.05 equiv) and the mixturestirred at r.t. for 2 h, then evaporated. The title compound wasobtained as a white solid by crystallisation from ethanol (550 mg, 91%).

α!_(D) =+123.4 (c=0.316, CHCl₃).

¹ H NMR (270 MHz, CDCl₃) δ 8.78 (1H, d, J=2 Hz); 8.27 (1H, d, J=8 Hz);7.95 (1H, m); 7.65-6.6 (1 1H, m); 5.83 (1H, d, J=8 Hz); 5.05 (1H, d,J=16 Hz); 4.60 (1H, d, J=16 Hz); 3.0 (6H, s); 1.40 (9H, s) ppm.

Mass Spec (+FAB): M+H!⁺ =513.4.

EXAMPLE 23 3-(Formylamino)benzoic acid

Acetic anhydride (76 ml) was added to 98% formic acid (130 ml) and themixture stirred at r.t. 30 min, then 3-aminobenzoic acid (15 g, 109.5mmol) added. The mixture was stirred at r.t. for 1 h, then water (1.3 L)added and stirring continued overnight. The resultant white precipitatewas collected, washed with water and dried in vacuo over P₂ O₅ (15.4 g,85%).

EXAMPLE 24 N-Formyl-N-methylamino benzoic acid

3-Formylamino benzoic acid (2.28 g, 13.8 mmol) was taken up in DMF (25ml) and added dropwise to a suspension of sodium hydride (1.05 g, 80%disp. in oil) in DMF (15 ml) at 0° C. The mixture was allowed to warm tor.t. over 1 h and then iodomethane (0.95 ml) added. A second portion ofiodomethane (0.95 ml) was added after 1 h and the mixture stirred atr.t. overnight. The solvent was removed by evaporation and the productpartitioned between ethyl acetate and 1M HCl. The organic layer waswashed with brine, then filtered (Whatman® 1 PS phase separator) andevaporated. The residue was chromatographed on silica (eluant 60% ethylacetate in hexanes) to provide the title compound as a colourless solid(2.30 g, 86%). A portion of the ester (900 mg, 4.66 mmol) was taken upin dioxan/water (2/1, v/v, 30 ml) and treated with LiOH.H₂ O (378 mg, 9mmol) at r.t. with stirring overnight. The mixture was acidified with 1MHCl and extracted twice with EtOAc. The combined extracts were washedwith brine, filtered (Whatman® 1 PS phase separator) and evaporated. Theacid (420 mg, 50%) was used in the next step without furtherpurification.

EXAMPLE 25N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-(N-formyl-N-methylaminophenyl)urea

The benzoic acid derivative of Example 11 (210 mg, 1.15 mmol) wassuspended in toluene (25 ml) and treated with triethylamine (165 μl,1.65 mmol) and diphenylphosphoryl azide (270 μl, 1.25 mmol) undernitrogen. The mixture was stirred at r.t. 1 h, then heated at refluxovernight. The mixture was cooled and evaporated and a solution of theme of Example 5 (250 mg, 0.71 mmol) added in DCM (8 ml). The resultantmixture was stirred at r.t. for 6 h, then evaporated and chromatographedon silica (eluant 80/20 EtOAc/hexane→neat EtOAc) to provide the titlecompound as a pale yellow solid (185 mg, 50%).

¹ H NMR (270 MHz, CDCl₃) δ 8.62 (1H, d, J=2 Hz); 8.42 (1H, s); 8.01 (1H,d, J=8 Hz); 7.79 (1H, t, J=8 Hz); 7.15-6.70 (10H, m); 6.78 (1H, d, J=7Hz); 5.76 (1H, d, J=7 Hz); 5.01 (1H, d, J=17 Hz); 4.63 (1H, d, J=17 Hz);3.21 (3H, s); 1.36 (9H, s) ppm.

EXAMPLE 26N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-(methylamino)phenyl)urea

The benzodiazepine of Example 25 (185 mg, 0.35 mmol) was taken up inacetone (5 ml) and treated with 4M HCl (3 ml). The mixture was stirredovernight at r.t., then evaporated and partitioned between DCM and 5%KHCO₃. The organic portion was filtered (Whatman® 1 PS phase separator),evaporated and chromatographed on silica (eluant 120/2/1, v/v/v,chloroform/methanol/acetic acid) to provide a colourless solid (67 mg,88%).

¹ H NMR (270 MHz, CDCl₃) δ 8.69 (1H, d, J=2 Hz); 8.24 (1H, d, J=8 Hz);7.82 (1H, t, J=8 Hz); 7.59 (1H, t, J=8 Hz); 7.46-7.0 (9H, m); 6.80 (1H,br.s); 6.58 (1H, d, J=8 Hz); 6.37 (1H, d, J=8 Hz); 5.80 (1H, d, J=8 Hz);4.99 (1H, d, J=17 Hz); 4.58 (1H, d, J=17 Hz); 2.82 (3H, s); 1.30 (9H, s)ppm.

Mass Spec (+ve FAB): M+H!⁺ =499.3.

EXAMPLE 27 3-(tert-Butyloxycarbonylamino)benzoic acid

3-Aminobenzoic acid (4.11 g, 30 mmol) was taken up in 2M KOH (30 ml) anddioxan (30 ml). The solution was cooled to 0° C. anddi-tert-butyldicarbonate (6.98 g, 32 mmol) added. The mixture wasallowed to warm to r.t. and stirred overnight. Dioxan was removed byevaporation and the solution diluted with 1H KOH (50 ml). The mixturewas washed with ether (×2) and acidified with conc. HCl. The resultantwhite precipitate was collected by filtration and dried over P₂ O₅ (5.35g, 75%).

EXAMPLE 28N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pryridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-aminophenyl)urea

The benzoic acid derivative of Example 27 (1.19 g, 5 mmol) was taken upin benzene (20 ml) and triethylamine (1.2 ml) and treated withdiphenylphosphoryl azide (2.25 g). The mixture was heated at 80° C.overnight then cooled and evaporated. The chiral amine of Example 6 (850mg, 2.43 mmol) was added in CHCl₃ (10 ml) and the mixture stirred atr.t. for 3 h. The mixture was evaporated and chromatographed on silica(eluant 70% EtOAc in hexanes→EtOAc) to provide a colourless oil (1.4 g).This residue was taken up in DCM (10 ml) and treated with TFA (30 ml) atr.t. for 45 min under nitrogen. The mixture was evaporated andpartitioned between EtOAc and 5% KHCO₃. The organic portion was filtered(Whatman 1 PS, phase separator), evaporated and chromatographed (eluant6% MeOH in CHCl₃) to provide a hygroscopic colourless solid (788 mg,67%).

¹ H NMR (270 MHz, CDCl₃) δ 8.59 (1H, d, J=2 Hz); 8.08 (1H, d, J=8 Hz);7.62 (1H, t, J=8 Hz); 7.44 (1H, t, J=8 Hz); 7.4-6.8 (12H, m); 5.68 (1H,d, J=8 Hz); 4.80 (1H, d, J=16 Hz); 4.60 (1H, d, J=16 Hz); 1.40 (9H, s)ppm.

Mass Spec (+ve FAB): M+H!⁺ =485.3.

EXAMPLE 29 3-Phenacyl pyridazine

3-Phenacyl pyridazine was prepared in 53% yield according to the methodoutlined in Example 5A.

EXAMPLE 30 3-((2-Benzoylamino)benzoyl)pyridazine

The ketone of Example 29 (5.5 g, 27.8 mmol) and fleshly distilled phenylhydrazine (2.75 ml, 27.8 mmol) were stirred together in refluxingtoluene under Dean-Stark conditions for 4 h. Zinc chloride (2.5 g) wasadded and reflux continued overnight. The stirring mixture was allowedto cool to r.t. and the resultant precipitate filtered to provide thecrude indole as a mixture with zinc salts (9.25 g). The crude product (3g) was taken up in acetic acid (80 ml), CrO₃ (4.8 g) added and themixture stirred at 70° C. for 3 h, then cooled, basified with 3M KOH andextracted with EtOAc. The combined extracts were dried (MgSO₄) andchromatographed on silica (eluant 80% EtOAc in hexanes) to provide ayellow solid (1.46 g, 44%, two steps).

¹ H NMR of crude indole (270 MHz, d₆ DMSO) δ 11.90 (1H, br.s); 9.07 (1H,dt, J_(d) =8 Hz, J_(t) =1.5 Hz); 7.95 (1H, d, J=8 Hz); 7.6-7.3 (8H, m);7.23 (1H, t, J=8 Hz); 7.14 (1H, t, J=8 Hz) ppm.

¹ H NMR of 3-(2-Aminobenzoyl) pyridazine (270 MHz, CDCl₃) δ 12.16 (1H,br.s); 9.34 (1H, dd, J₁ =5 Hz, J₂ =1.5 Hz); 8.97 (1H, d, J=8 Hz);8.10-7.40 (9H, m); 7.15 (1H, t, J=8 Hz) ppm.

EXAMPLE 31 3-(2-Aminobenzoyl)pyridazine

The benzamide of Example 30 (700 mg, 2.31 mmol) was taken up in ethanol(8 ml) and treated with 5M KOH (20 ml) at 80° C. for 4 h. The mixturewas cooled, diluted with 5% KHCO₃ and extracted with EtOAc. The extractswere filtered (Whatman® 1 PS, phase separator) and evaporated and theresidue chromatographed (eluant 70% EtOAc in hexanes) to provide thetitle compound as a yellow crystalline solid (160 mg, 32%).

¹ H NMR (270 MHz, CDCl₃) δ 9.30 (1H, dd, J₁ =5 Hz, J₂ =1.5 Hz); 7.90(1H, dd, J₁ =7.5 Hz, J₂ =1.5 Hz); 7.75 (1H, d, J=7.5 Hz); 7.68 (1H, m);7.33 (1H, m); 6.73 (1H, d, J=9 Hz); 6.62 (1H, t, J=7.5 Hz); 6.40 (2H,br.s) ppm.

EXAMPLE 32(3RS)-Benzyloxycarbonylamino-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-2-one

The title compound was prepared from the amino ketone of Example 31 (160mg, 0.805 mmol) as described in Example 1C. The product was purified bycrystallisation from EtOAc/ether/hexane to provide a pale yellow solid(91 mg, 30%).

¹ H NMR (270 MHz, CDCl₃) δ 9.25 (1H, dd, J₁ =5 Hz, J₂ =1.5 Hz); 8.34(1H, d, J=8 Hz); 8.19 (1H, br.s); 7.63-7.24 (9H, m); 7.12 (1H, d, J=8Hz); 6.69 (1H, d, J=8 Hz); 5.47 (1H, d, J=8 Hz); 5.17 (2H, s) ppm.

EXAMPLE 33(3RS)-Benzyloxycarbonylamino-1-tert-butylcarbonylmethyl-2,3-dihydro-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-2-one

The benzodiazepine of Example 32 (85 mg, 0.2196 mmol) was alkylated with1-bromopinacolone as described in Example 1D. The product waschromatographed on silica (eluant EtOAc) to provide a yellow solid (75mg, 70%).

¹ H NMR (270 MHz, CDCl₃) δ 9.23 (1H, dt, J_(t) =5 Hz, J_(d) =1.5 Hz);8.37 (1H, d, J=9.5 Hz); 7.62-7.50 (3H, m); 7.37-7.23 (6H, m); 7.13 (1H,d, J=8 Hz); 6.75 (1H, d, J=8 Hz); 5.57 (1H, d, J=8 Hz); 5.14 (2H, s);5.01 (1H, d, J=17.8 Hz); 4.46 (1H, d, J=17.8 Hz); 1.25 (9H, s) ppm.

EXAMPLE 34N-((3RS)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(3-pyridazinyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea

The title compound was prepared from the benzodiazepine of Example 33(70 mg, 0.144 mmol) by the method described in Examples 5F and 6. Theproduct was purified by chromatography (eluant 3% MeOH in EtOAc) and theresultant solid crystallised from MeCN/ether (12 mg, 17%).

¹ H NMR (270 MHz, CDCl₃) δ 9.19 (1H, d, J=5 Hz); 8.33 (1H, d, J=8.5 Hz);7.6-7.48 (2H, m); 7.30-7.00 (6H, m); 7.90 (1H, br.s); 6.60-6.44 (2H, m);5.77 (1H, d, J=8 Hz); 4.95 (1H, d, J=18 Hz); 4.53 (1H, d, J=18 Hz); 2.91(6H, s); 1.22 (9H, s) ppm.

Mass Spec (+ve FAB): M+H!⁺ =514.5.

EXAMPLE 35 Methyl 3-(4-pentenoylamino)benzoate

Methyl(3-amino)benzoate (4.5 g, 29.8 mmol) was taken up in DCM (10 ml)and pyridine (1 ml) at 0° C. 4-Pentenoyl chloride (freshly prepared from4-pentenoic acid (3.0 g, 29.97 mmol) and thionyl chloride (6.6 ml) atr.t. for 1 h, evaporated and azeotroped with DCM) was added dropwise inDCM (3 ml). The mixture was allowed to warm to r.t. and stirredovernight. The mixture was evaporated and partitioned between EtOAc and1M HCl. The organic portion was washed with 5% KHCO₃ and brine, filtered(Whatman® 1PS, phase separator), and evaporated. The residue waschromatographed (eluant 30% EtOAc in hexanes) to provide a colourlessoil (2.20 g, 32%).

¹ H NMR (270 MHz, CDCl₃) δ 8.05 (1H, t, J=1.5 Hz); 7.93 (1H, d, J=8 Hz);7.79 (1H, d, J=8 Hz); 7.56 (1H, br.s); 7.42 (1H, t, J=8 Hz); 5.92 (1H,m); 5.2-5.0 (2H, m); 3.93 (3H, s); 2.51 (4H, m) ppm.

EXAMPLE 36 Methyl 3-(5-bromopentanoylamino)benzoate

The compound of Example 35 (1.7 g, 7.3 mmol) was taken up in dry THf (25ml) at r.t. under nitrogen. 9-BBN (20 ml, 0.5M solution) was added andthe mixture stirred at r.t. for 3 h. 1M NaOH (8 ml) was then addedfollowed by 27% hydrogen peroxide (2.5 ml, dropwise). Stirring wascontinued at 40° C. for 1 h, then the mixture evaporated, taken up inEtOAc and washed with 5% KHCO₃ and brine. The organic portion wasfiltered (Whatman® 1 PS, phase separator), evaporated andchromatographed (eluant 95% EtOAc in hexanes) to provide the alcohol asa mixture with borates. The product was taken up in DCM (120 ml) andtreated with triphenyl phosphine (5 g) and carbon tetrabromide (6.2 g)at r.t. for 2 h with stirring. The mixture was then evaporated andchromatographed (eluant 40% EtOAc in hexanes) to provide a colourlessoil which crystallised on standing (1.54 g, 67%).

¹ H NMR (270 MHz, CDCl₃) δ 9.62 (1H, br.s); 8.26 (1H, t, J=1.5 Hz);7.95-7.8 (2H, m); 7.4 (1H, m); 3.96 (3H, s); 3.44 (2H, m); 2.66 (2H, m);1.98 (4H, m) ppm.

EXAMPLE 37 Methyl 3-(2-oxo-1-piperidinyl)benzoate

The bromide of Example 36 (1.50 g, 4.88 mmol) was taken up in dry DMF(40 ml) and treated with NaH (160 mg, 80% disp. in oil) at 0° C. Themixture was stirred at r.t. under nitrogen for 10 min, then KI (80 mg)added and the mixture heated at 70° C. for 4 h. The mixture wasevaporated and partitioned between EtOAc and 1M HCl. The organic portionwas washed with 5% KHCO₃ and brine, filtered (Whatman® 1 PS, phaseseparator) and evaporated. The residue was chromatographed (eluant 2%MeOH in EtOAc) to provide a colourless oil (640 mg, 56%).

¹ H NMR (270 MHz, CDCl₃) δ 8.1-7.95 (2H, m); 7.60-7.50 (2H, m); 3.98(3H, s); 3.75 (2H, m); 2.64 (2H, m); 2.03 (4H, m) ppm.

EXAMPLE 38 Methyl 3-(1-piperidinyl)benzoate

The compound of Example 37 (640 mg, 2.75 mmol) was dissolved in dry THF(30 ml) and borane-tetrahydrofuran complex (5 ml, 1M solution in THF)was added. The mixture was stirred under nitrogen under reflux for 1 h,then cooled and evaporated. The residue was taken up in MeOH/acetic acid(6/1, v/v, 70 ml) and heated under reflux for 3 h, then evaporated andchromatographed (eluant 10% EtOAc in hexanes) to provide a colourlessoil (540 mg, 90%).

¹ H NMR (270 MHz, CDCl₃) δ 7.59 (1H, t, J=1.5 Hz); 7.46 (1H, dd, J₁ =8Hz, J₂ =1.5 Hz); 7.28 (1H, t, J=8 Hz); 7.11 (1H, m); 3.89 (3H, s); 3.18(2H, m); 1.75-1.62 (4H, m); 1.61-1.55 (2H, m) ppm.

EXAMPLE 39 3-(1-Piperidinyl)benzoic acid

The compound of Example 38 (540 mg, 2.466 mmol) was dissolved in dioxan(12 ml) and water (8 ml). Lithium hydroxide hydrate (300 mg, 7.143 mmol)was added and the mixture stirred at 40° C. for 1 h. The mixture wasacidified with acetic acid, evaporated, azeotroped with toluene andchromatographed on silica (eluant 60/40/2, v/v/v, EtOAc/hexanes/AcOH) toprovide a colourless solid (450 mg, 90%).

¹ H NMR (270 MHz, CDCl₃) δ 7.66 (1H, s); 7.54 (1H, d, J=8 Hz); 7.32 (1H,t, J=8 Hz); 7.17 (1H, dd, J₁ =8 Hz, J₂ =1.5 Hz); 3.22 (4H, m); 1.72 (4H,m); 1.61 (2H, m) ppm.

EXAMPLE 40N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-(1-piperidinyl)phenyl)urea

3-(1-Piperidyl)benzoic acid (225 mg, 1.097 mmol) was converted to theisocyanate using the method described in Example 2. To a solution of theisocyanate in DCM (5 ml) was added the benzodiazepine of Example 19 (220mg, 0.6286 mmol). The mixture was stirred at r.t. for 1 h, thenevaporated and chromatographed (eluant 90% EtOAc in hexanes) to providea white solid which was recrystallised from MeCN (180 mg, 52%).

α!_(D) =+117° (c=0.296, CHCl₃).

¹ H NMR (270 MHz, CDCl₃) δ 8.59 (1H, d, J=6 Hz); 8.15 (1H, d, J=8 Hz);7.75 (1H, t, J=6 Hz); 7.50 (1H, t, J=6 Hz); 7.4-6.9 (8H, m); 6.61 (2H,m); 5.73 (1H, d, J=8 Hz); 4.96 (1H, d, J=17.5 Hz); 4.50 (1H, d, J=17.5Hz); 3.12 (4H, m); 1.73-1.52 (6H, m); 1.22 (9H, s) ppm.

Mass Spec (+ve FAB) M+H!⁺ =553.4.

EXAMPLE 41(3RS)-tert-Butyloxycarbonylamino-2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodiazepin-2-one

tert-Butylcarbamate (15 g), benzotriazole (15.26 g) and glyoxilic acidhydrate (11.8 g) were mixed together in benzene (250 ml) and heatedunder reflux with the aid of a Dean-Stark separator as described(Katritsky, J Org Chem 1990, 55, 2266).

The mixture was cooled and extracted twice with 5% NaHCO₃ and thecombined aqueous extracts washed with ether then acidified and extractedwith EtOAc. The EtOAc extracts were washed with brine, dried (MgSO₄) andevaporated. The residue was (taken up in DCM (80 ml) and treated withDMAP (0.4 g) and 2-aminobenzophenone (8 g, 40.4 mmol). The mixture wascooled to 0° C. with stirring and water soluble carbodiimide (10 g)added. Stirring was continued at r.t. for 3 h, after which time themixture was evaporated and partitioned between EtOAc and 5% KHCO₃. Theorganic portion was washed with 1M HCl and brine, dried and filtered(Whatman® 1 PS phase separator) then evaporated to dryness. The residuewas taken up in an ice-cold saturated solution of ammonia in methanol,stoppered and stirred at r.t. for 45 min. The mixture was re-cooled andevaporated. The residue was suspended in ether 100 ml and 1M HCl (250ml). The ether was decanted and the aqueous portion basified andextracted with EtOAc (×2). The combined extracts were washed with brine,dried (MgSO₄) and evaporated. The resultant solid was recrystallisedfrom EtOAc/hexanes to provide a white solid (8.62 g, 61%).

¹ H NMR (270 MHz, CDCl₃) δ 8.41 (1H, br.s); 7.60-7.14 (9H, m); 6.36 (1H,d, J=8.8 Hz); 5.32 (1H, d, J=8.8 Hz); 1.48 (9H, s).

EXAMPLE 42N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea

The chiral (R)-amine of Example 19 (750 mg, 2.14 mmol) was taken up indry DCM (10 ml) at 0° C. and treated with m-tolylisocyanate (0.33 ml,2.57 mmol). The mixture was stirred at r.t. for 2 h, then evaporated andchromatographed on silica (eluant 70% EtOAc in hexanes). The residue wasrecrystallised from EtOAc/hexane to provide a white crystalline solid(955 mg, 92%).

Mass Spec (+ve FAB): M+H!⁺ =484.2.

¹ H NMR (270 MHz, CDCl₃) δ 8.79 (1H, d, J=3 Hz); 8.30 (1H, d, J=8 Hz);7.96 (1H, t, J=8 Hz); 7.63 (1H, t, J=8 Hz); 7.55-6.95 (10H, m); 5.83(1H, d, J=8 Hz); 5.08 (1H, d, J=17 Hz); 4.71 (1H, d, J=17 Hz); 2.41 (3H,s); 1.38 (9H, s) ppm.

α!_(D) =+119.8° (c=0.272, CHCl₃).

EXAMPLE 43 Ethoxycarbonyl-(1-benzotriazolyl)glycine

(Alternative procedure to Example 14)

Ethyl carbamate (69.0 g, 774.5 mmol), glyoxylic acid hydrate (71.3 g,774.5 mmol) and benzotriazole (92.0 g, 774.5 mmol) were dissolved intoluene (2.3 1) and the mixture was heated with distillation for 3 h toprecipitate the product. The mixture was diluted with toluene (totally2.3 1) and stirred at 15° C. overnight. The resultant precipitate wascollected by filtration, washed with toluene (160 ml) and dried toafford the title compound (196.06 g, 96%): mp. 189°-192° C.

EXAMPLE 44 2-(2-Aminobenzoyl)pyridine

(Alternative procedure to Example 15)

2-Aminobenzonitrile (58.3 g, 493.6 mmol), and 2-bromopyridine (132.5 g,838.6 mmol) were dissolved in toluene (875 ml) and the mixture wascooled below -30° C. under nitrogen. ^(n) BuLi (15% solution in ^(n)hexane; 700 ml, 1.09 mol) was added dropwise to the mixture below -30°C. The mixture was allowed to warm to 0° C. and stirring was continuedfor 1.5 h. The mixture was poured into 3M HCl (800 ml) below 15° C. andstirred for 15 min. The separated organic portion was extracted with 3MHCl (200 ml). The combined aqueous portions were washed with toluene(200 ml), basified to pH 9 with 25% NaOH below 5° C. and stirred at r.t.overnight. The resultant precipitate was collected by filtration, whichwas recrystallised from isopropanol (880 ml) to afford the titlecompound (70.05 g, 72%): mp. 145°-146° C.

EXAMPLE 45(3RS)-Ethoxycarbonylamino-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(Alternative procedure to Example 16, using DCC instead of WSC andDMAP.)

2-(2-Aminobenzoyl)pyridine (56.4 g, 284.5 mmol) andEtOC-(1-benzotriazolyl)glycine (94.1 g, 356.1 mmol) were combined in DCM(850 ml). A solution of DOC (83.8 g, 406.1 mmol) in DCM (80 ml) wasadded dropwise at 0°-5° C. and the mixture was stirred for 1 h. 5%NaHCO₃ (1 l) was added to the mixture and stirring was continued for 1h. The resultant precipitate was filtered off and the organic portionwas washed with brine (600 ml) and concentrated to ca. 300 ml. Themixture was diluted with methanol (500 ml) and concentrated to ca. 500ml.

20% ammonia in methanol (600 ml) was added to the solution below 5° C.and the mixture was stirred below 10° C. for 3 h. Acetic acid (500 ml)was added to the solution below 15° C., and the mixture was stirred at0° C. overnight and evaporated. CHCl₃ (1.5 l) and water (500 ml) wereadded to the residue and basified to pH 9 with 25% NaOH. The organicportion was washed with brine (700 ml) and concentrated to ca. 500 ml.The mixture was diluted with EtOAc (1.5 l), concentrated to ca. 1.5 l atatmospheric pressure and stirred at 0° C. overnight. The resultantprecipitate was collected by filtration to afford the title compound(70.55 g, 77%): mp. 220°-223° C.

EXAMPLE 46(3RS)-Ethoxycarbonylamine-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(Minor changes to Example 17)

(3RS)-Ethoxycarbonylamino-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one(14.6 g, 45.0 mmol) was taken up in dry DMF (73 ml). Sodium hydride (1.4g, 58.5 mmol) was added portionwise below 5° C. and the mixture wasstirred at r.t. for 1 h. 1-Bromopinacolone (10.21 g, 57.0 mmol) was thenadded dropwise below 10° C. and stirring was continued at r.t for 1 h.The mixture was evaporated, taken up in DCM (73 ml) and washed with 5%NaHCO₃ and brine. The organic portion was evaporated and recrystallisedfrom EtOAc/hexane (1:1, v/v, 146 ml) to provide the title compound as awhite solid (15.4 g, 81%): top. 214°-216° C.

EXAMPLE 47(3RS)-Amino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one

(Alternative to Example 18, using TMS-I instead of HBr to give higheryield with clean reaction)

Hexamethyldisilane (4.36 g, 29.8 mmol) was added dropwise to thesuspension of iodine (7.51 g, 29.6 mmol) in DCM (27 ml) at 30°-35° C.and the mixture was stirred at 30° C. for 1 h.

A solution of(3RS)-ethoxycarbonylamino-1-(tert-butylcarbonylmethyl)-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one(10.0 g, 23.7 mmol) in DCM (40 ml) was added to the above solution below25° C. and the mixture was stirred for 50 h. The mixture was then pouredinto 3M HCl (80 ml) below 25° C. and the aqueous portion was washed withDCM (10 ml×2). The combined organic portions were extracted with 3M HCl(20 ml). DCM (50 ml) was added to the combined aqueous portions and themixture was basified to pH 10 with 25% NaOH below 5° C. The organicportion was washed with brine (50 ml) and evaporated. CH₃ CN (50 ml) wasadded and the mixture was filtered to remove the small amount ofinsoluble material. The filtrate was evaporated to give the riflecompound as a brown foam (7.75 g, 93%), which was not purified further.

Example 48 3-tert-Butoxycarbonylaminobenzoic acid

(Minor changes to Example 27)

3-Aminobenzoic acid (24.69 g, 180.0 mmol) was taken up in 2M KOH (180ml) and dioxane (180 ml), and treated with di-tert-butyl dicarbonate(53.03 g, 245.0 mmol) at r.t. overnight. Dioxane was removed byevaporation and the solution was diluted with 1M KOH (300 ml). Theaqueous portion was washed with ether (200 and 300 ml) and acidified topH 4 with conc. HCl. The resultant white precipitate was collected byfiltration, washed with water and dried in vacuo (P₂ O₅) to give thetitle compound (38.97 g, 91%).

EXAMPLE 49N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)ureahydrochloride

N-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-dimethylaminophenyl)urea(70 g, 136.6 mmol) was taken up in ethanol (1 l) and 2.26M HCl ethanol(63.5 ml, 143.4 mmol) was added dropwise. The mixture was warmed up to50° C. to afford a clear solution, which was seeded, cooled to 0° C. andstirred at the same temperature overnight. The resultant precipitate wascollected by flirtation to provide the title compound as a whitecrystalline (62.4 g, 82%): top. 181°-184° C.

¹ H NMR (400 MHz, DMSO-d₆) δ 9.46 (1H, br.s); 8.61 (1H, d, J=5 Hz); 8.02(2H, m); 7.66 (3H, m); 7.57 (1H, t, J=6 Hz); 7.45 (1H, d, J=8 Hz); 7.34(3H, m); 7.20 (1H, br.s); 7.07 (1H, br.s); 5.41 (1H, d, J=8 Hz); 5.05(1H, d, J=18 Hz); 4.85 (1H, d, J=18 Hz); 3.02 (6H, s); 1.17 (9H, s) ppm.

EXAMPLE 50 3-(N-tert-Butoxylcarbonyl-N-methylamino)benzoic acid

Sodium hydride (18.33 g, 60% disp. in oil, 458.3 mmol) was addedportionwise to a solution of 3-tert-butoxycarbonylaminobenzoic acid(43.48 g, 183.3 mmol) in DMF (600 ml) below 10° C. and the mixture wasallowed to warm to r.t. with stirring over 1 h. MeI (84.54 g, 595.6mmol) was added dropwise to the solution for 30 min at 5° C. and themixture was stirred at r.t. for 2 h. The mixture was evaporated and theresidue was partitioned between EtOAc (1.2 l) and water (600 ml). Theorganic portion was washed with sat. NaHCO₃ (100 ml) and water (200ml×5), dried (MgSO₄) and evaporated.

The residual oil was taken up in methanol (1 l), 1M LiOH (185 ml) wasadded to the solution at 5° C. and the mixture was stirred at r.t. for12 h. A further 1M LiOH (90 ml) was added to the mixture and stirred for1 h. The solution was evaporated to remove methanol, diluted with waterand washed with EtOAc/hexane (1:2, v/v, 300 and 150 ml). The aqueousportion was acidified to pH 4 with cone. HCl and extracted with EtOAc(400 and 200 ml). The combined organic portions were washed with brine,dried (MgSO₄) and evaporated. The residue was recrystallised fromEtOAc/hexane (1:20, v/v, 420 ml) to give the title compound (36.08 g,78%).

EXAMPLE 51 3-(N-tert-Butoxylcarbonyl-N-methylamino)phenyl isocyanate

Et₃ N (3.71 g, 36.7 mmol) and a solution of ethyl chloroformate (4.31 g,39.7 mmol) in acetone (10 ml) were successively added dropwise to asolution of 3-(N-tert-butoxylcarbonyl-N-methylamino)benzoic acid (8.0 g,31.8 mmol) in acetone (64 ml) below 5° C. After stirring for 30 min, asolution of NaN₃ (3.10 g, 47.7 mmol) in water (10 ml) was added to thesolution below 5° C. The mixture was stirred at the same temperature fora further 1 h, then poured into toluene (80 ml) and water (160 ml). Theorganic portion was washed with brine, refluxed for 2 h and evaporated.The residue was distilled (100°-105° C./0.9-1.0 mmHg) to afford thetitle compound (6.2 g, 78%) as a yellow oil.

EXAMPLE 52N(-((3R)-1-tert-Butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-3-methylaminophenyl)urea

3-(N-tert-Butoxylcarbonyl-N-methylamino)phenyl isocyanate (19.30 g, 77.7mmol) was added dropwise to a solution of the chiral-amine of Example 19(27.19 g, 77.6 mmol) in DCM (200 ml) below 20° C. and the mixture wasstirred at r.t. for 30 min, then evaporated. The residue was taken up inEtOAc (200 ml) and water (100 ml), cone. HCl (120 ml) was added dropwiseto the mixture below 20° C. and stirred for 3 h. DCM (500 ml) was addedto the separated aqueous portion and basified to pH 10 with 20% NaOHbelow 20° C. The organic portion was washed with brine (300 ml),evaporated and crystallised from ethanol. The resultant precipitate wascollected by flirtation and recrystallised from ethanol (1.8 l) toprovide the title compound as a white crystalline (27.30 g, 72%): mp.243°-246° C.

¹ H NMR (400 MHz, CDCl₃) δ 8.60 (1H, d, J=5 Hz); 8.15 (1H, d, J=8 Hz);7.77 (1H, dt, J_(t) =8 Hz, J_(d) =1.5 Hz) 7.51 (1H, dt, J_(t) =8 H,J_(d) =1.5 Hz) 7.39-6.76 (9H, m); 6.54 (1H, d, J=8Hz); 6.30 (1H, dd,J=8, 1.5 Hz); 5.72 (1H, d, J=8 Hz); 4.96 (1H, d, J=18 Hz); 4.54 (1H, d,J=18 Hz); 2.78 (3H, s); 1.23 (9H, s) ppm.

Mass Spec (+ve FAB): M+H!⁺ =499.

The compounds of and prepared by the present invention are potent andselective antagonists at the CCK-B receptor and inhibit gastric acidsecretion stimulated by pentagastrin. Methods of measuring theseactivities are described below.

Measurement of binding affinity for CCK-B receptors

About 100 SD rats were decapitated without anaesthesia, the whole brainwas immediately excised from each of the rats and homogenized in 10-foldvolume of 0.32M aqueous solution of sucrose by the use of aTeflon-coated homogenizer, the homogenate thus obtained was centrifugedfor ten minutes at 900 G by the use of a cooled centrifuge, and thesupernatant was further centrifuged for 15 minutes at 11500 G. Theprecipitate thus obtained was dispersed in 50 mM Tris-HCl buffer (pH7.4) containing 0.08% Triton X-100, this suspension was allowed to standfor 30 minutes and again centrifuged for 15 minutes at 11500 G, theprecipitate thus obtained was washed twice with 5 mM Tris-HCl buffer andtwice with 50 mM Tris-HCl buffer in that order with centrifugalseparation, the washed precipitate was suspended in 50 mM Tris-HClbuffer, and the suspension thus obtained was stored at -80° C. until themembrane preparation was required.

The membrane preparations were warmed to room temperature, diluted with10 mM HEPES buffer (containing 130 mM NaCl, 5 mM MgCl₂, 1 mM EGTA and0.25 mg/ml bacitracin; pH 6.5) and incubated at 25° C. for 120 minutesin the presence of ¹²⁵ I!BH-CCK-8 and the test compound, then separatedby suction filtration. Non-specific binding was determined in thepresence of 1 μM CCK-8. The amount of labelled ligand bound to thereceptor was measured by the use of a γ-counter, IC₅₀ values weredetermined, being that concentration of test compound required toinhibit specific binding by 50%.

IC₅₀ values for the compounds of this invention were in the range 0.1 to<100 nM; representative examples are shown below.

    ______________________________________                                                          IC.sub.50 (nM)                                              ______________________________________                                        Compound of Example 281 of                                                                        29.0                                                      U.S. Pat. No. 4,820,834                                                       Compound of Example 22                                                                            0.20                                                      Compound of Example 26                                                                            1.4                                                       Compound of Example 2                                                                             2.08                                                      Compound of Example 4                                                                             0.63                                                      Compound of Example 50                                                                            0.88                                                      Compound of Example 6                                                                             0.22                                                      Compound of Example 8B                                                                            55.3                                                      Compound of Example 42                                                                            0.44                                                      ______________________________________                                    

Determination of selectivity for the CCK-B receptor by comparison withbinding to the CCK-A receptor in rats

The pancreas of an SD rat was homogenized in a 20-fold volume of 50 mMTris-HCl buffer (pH 7.7) by the use of a Polytrone-type homogenizer, thehomogenate was twice centrifuged for 10 minutes at 50000 G by the use ofan ultra-centrifuge, the precipitate thus obtained was suspended in a40-fold volume of 50 mM Tris-HCl buffer (containing 0.2% BSA, 5 mMMgCl₂, 0.1 mg/ml bacitracin and 5 mM DTF; pH 7.7), and the suspensionwas stored at -80° C. until the membrane preparations were required.

The membrane preparations were then warmed to room temperature, diluted1:10 with the buffer and incubated at 37° C. for 30 minutes in thepresence of ³ H!L-364,718 and the test compound then separated bysuction filtration. Non-specific binding was determined in the presenceof 1 μM L-364,718. The amount of labelled ligand bound to the receptorwas measured by the use of a liquid scintillation counter, IC₅₀ valueswere determined, being that concentration of test compound required toinhibit specific binding by 50%.

A high affinity for the CCK-A receptor in a CCK-B/gastrin antagonist isthought to be undesirable as it may lead to side-effects such ascholestasis and gall stone formation during therapy. Therefore it ispreferable for the therapeutic agent to be selective for the CCK-Breceptor. This selectivity is expressed by the ratio IC₅₀ (CCK-A)/IC₅₀(CCK-B); the higher the value of this ratio the better is theselectivity.

The table below summarises CCK-B and CCK-A binding data for examples ofpreferred compounds, as well as the A/B ratio. Many compounds display amarked increase in CCK-B receptor bin dine affinity when compared to thecompound of Example 281 of U.S. Pat. No. 4,820,834 (also known asL-365,203). Several compounds also show greater selectivity for theCCK-B receptor over the CCK-A receptor than that reported for thecompound of Example 281 of U.S. Pat. No. 4,820,834.

    ______________________________________                                                        Receptor binding affinity IC.sub.50 (nM)                      Compound          CCK-B    CCK-A    A/B Ratio                                 ______________________________________                                        Compound of Example 281                                                                         29       12,000   410                                       of U.S. Pat. No. 4,820,834                                                    Compound of Example 1                                                                           4.52     844      187                                       Compound of Example 2                                                                           2.08     495      238                                       Compound of Example 3                                                                           0.80     433      540                                       Compound of Example 4                                                                           0.63     441      700                                       Compound of Example 22                                                                          0.20     113      565                                       Compound of Example 52                                                                          0.10     502      5020                                      ______________________________________                                    

Measurement of inhibition of pentagastrin-stimulated gastric acidsecreation in rat

A cannula was inserted into the trachea of a rat anaesthetised withurethane (intraperitoneally administered, 1.25 g/Kg), its abdominal wallwas incised to expose the gastric and duodenal portions, and apolyethylene cannula was set in the anterior stomach after ligation ofthe cardia. The duodenum was then subjected to slight section, apolyethylene cannnula was inserted from the incised portion toward thestomach, and the pylorus was ligated to fix the cannula.

Physiological saline (with pH adjusted to 7.0) was perfused from theanterior stomach toward the pylorus at a rate of 3 ml/min, and thegastric-acid secreation was measured by continuous titration of theperfusate by the use of a pH-stat (AUT-201; product of Toa Electronics,Ltd.). The continuous titration was carried out by using 25 mM NaOHsolution until the pH reached 7.0, and the result was expressed as theamount of gastric acid secreted for every 10 minutes (μE_(q) /10 min.).Pentagastrin was intravenously administered at a rate of 15 μg/Kg/hr.

The secretion of gastric acid increased upon administration ofpentagastrin, reaching the maximum level after 60 minutes and stablymaintaining this level after that. A test drug was then intravenouslyadministered, and the secretion of gastric acid was measured; ED₅₀values were determined, being the mount of the drug required to reducethe mount of secreted gastric acid down to 50% of the maximum level.

Relative ED₅₀ values are shown below.

    ______________________________________                                                          ED.sub.50 (μmol/kg)                                      ______________________________________                                        Compound of Example 281 of                                                                        4.2                                                       U.S. Pat. No. 4,820,834                                                       Compound of Example 22                                                                            0.011                                                     Compound of Example 42                                                                            0.016                                                     ______________________________________                                    

The ruble below shows the maximum inhibition observed for representativeexamples. Each result is a mean for 3-5 animals.

    ______________________________________                                                          % Inhibition at                                                               0.1 μmol/kg                                              ______________________________________                                        Compound of Example 281 of                                                                        28                                                        U.S. Pat. No. 4,820,834                                                                           (at 0.3 μmol/kg)                                       Compound of Example 1                                                                             48.9                                                      Compound of Example 2                                                                             47.4                                                      Compound of Example 3                                                                             57.6                                                      Compound of Example 4                                                                             55.2                                                      Compound of Example 5                                                                             55.4                                                      Compound of Example 6                                                                             61.9                                                      ______________________________________                                    

The experiments described above demonstrate that compounds of andprepared by the present invention are potent CCK-B antagonists and thatthey inhibit the stimulation of gastric acid release due topentagastrin. They are therefore useful in the treatment of diseasestates in which the CCK-B or gastrin receptor is implicated as amediating factor. Such disease states would include disorders of thegastro-intestinal system, for example gastric and duodenal ulceration,gastritis, reflux esophagitis, Zollinger-Ellison syndrome,gastrin-sensitive pancreas, and gastrin-sensitive tumors. Disorders ofthe central nervous system such as anxiety and psychoses would also beamenable to treatment with the compounds of this invention. Thecompounds can also be used in the control of appetite and pain.

The compounds of this invention and salts thereof can be administeredorally (including sublingual administration) or parenterally in the formof tablets, powders, capsules, pills, liquids, injections,suppositories, ointments and adhesive plasters.

The carrier and excipient for pharmaceutical manufacturing can be asolid or liquid, non-toxic medicinal substance, such as lactose,magnesium stearate, starch, talc, gelatin, agar, pectin, gum arabic,olive oil, sesame oil, cocoa butter, ethylene glycol and other commonlyemployed materials.

Examples of formulations using the compounds of this invention aredescribed below.

Examples of tablet preparation

    ______________________________________                                        Composition       20 mg-Tablet                                                                             40 mg-Tablet                                     ______________________________________                                        Compound of Example 4                                                                           20 mg      40 mg                                            Lactose           73.4       80                                               Corn Starch       18         20                                               Hydroxypropylcellulose                                                                          4          5                                                Carboxymethylcellulose Ca                                                                       4          4.2                                              Mg Stearate       0.6        0.8                                              Total             120 mg     150 mg                                           ______________________________________                                    

Preparation of 20 mg-tablets

Compound of Example 4 (100 g), lactose (367 g) and corn starch (90 g)were homogeneously mixed together by the use of a flow granulatingcoater (product of Ohgawara Seisakusho), 10% aqueous solution ofhydroxypropylcellulose (200 g) was sprayed into the mixture, andgranulation was then performed. After drying, the granules were filteredthrough a 20-mesh sieve, 20 g of carboxymethylcellulose Ca and 3 g ofmagnesium stearate were then added, and the mixture was treated in arotary tablet machine equipped with a pestle of 7 mm×8.4 R (product ofHam Tekkosho), thus producing tablets each weighing 120 mg.

Preparation of 40mg-tablets

Compound of Example 4 (140 g), lactose (280 g) and corn starch (70 g)were homogeneously mixed together by the use of a flow granulatingcoater (product of Ohgawara Seisakusho), 10% aqueous solution ofhydroxypropylcellulose (175 g) was sprayed into the mixture, andgranulation was then performed. After drying, the granules were filteredthrough a 20-mesh sieve, 14.7 g of carboxymethylcellulose Ca and 2.8 gof magnesium stearate were then added, and the mixture was treated in arotary tablet machine equipped with a pestle of 7.5 mm×9R (product ofHata Tekkosho), thus producing tablets each weighing 150 mg.

The clinical dosage of the compounds of this invention will bedetermined by the physician taking into account the precise illness, andthe body weight, age, sex, medical history and other factors of thepatient to be treated. In general the dosage when administered orallywill be between 1 and 1000 mg/day in either a single dose or sub-dividedinto smaller multiple doses.

We claim:
 1. A process for the production of benzodiazepines of generalformula V or pharmaceutically active salts thereof which comprises thecoupling reaction of an optionally substituted N-protectedα-(1-benzotriazolyl)glycine derivative (II) with an aromatic orheterocyclic amino ketone (III), followed by reaction of theintermediate (IV) with ammonia and then an acid catalyzed cyclisation ofthe resultant amino-ketone ##STR25## wherein: R² is an optionallysubstituted aromatic carbocyclic or heterocyclic group;R⁸ is a linear orbranched C₁ -C₆ alkyl, a C₃ -C₈ cycloalkyl, or an optionally substitutedaralkyl, optionally substituted aryl or heteroaryl group; R⁹ is H, alinear or branched C₁ -C₆ alkyl, or CH₂ COR⁴ where R⁴ is an alkyl, acycloalkyl, or an optionally substituted aryl, heteroaryl or saturatedheterocyclic group; X¹ is H, C.sub. -C₃ alkyl, C₁ -C₃ alkyloxy, F, Cl orBr; and Y is --O--, --NH-- or a single bond.
 2. A process according toclaim 1 in which:R⁸ is a linear or branched C₁ -C₆ alkyl, a C₃ -C₈cycloalkyl, or an optionally substituted benzyl, phenyl or heteroarylgroup; R⁹ is H or a linear or branched C₁ -C₆ alkyl; X¹ is H; and Y is--O--.
 3. A process including the steps of claim 1 for the production ofany of the following compounds or pharmaceutically acceptable saltsthereof:(a)N-((3R)-1-tert-butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-((3-dimethylamino)phenyl)urea; (b)N-((3R)-1-tert-butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methyl(formylamino)phenyl)urea; (c)N-((3R)-1-tert-butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-((3-methylamino)phenyl)urea; (d)N-((3R)-1-tert-butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-aminophenyl)urea; (e)N-((3R)-1-tert-butylcarbonylmethyl-2,3-dihydro-2-oxo-5-(2-pyridyl)-1H-1,4-benzodiazepin-3-yl)-N'-(3-methylphenyl)urea;and (f)(3RS)-(ethoxycarbonyl)amino-2,3-dihydro-5-(2-pyridyl)-1H-1,4-benzodiazepin-2-one.4. A process according to claim 1 which comprises the following reactionsequence: ##STR26## Reagents (a) ##STR27## WSCI, DMP; (b) NH₃ MeOH;(c)NH₄ OAc,AcHO; (d) NaH, DMF; (e) R⁴ COCH₂ Br; (f) HBr, DCM or H₂, Pd/C;(g) ##STR28## wherein: R² is an aromatic 5- or 6-membered substituted orunsubstituted heterocycle containing at least two heteroatoms of whichat least one is nitrogen, R⁴ is an alkyl, cycloalkyl or aryl group, andR¹⁰ is selected from the group consisting of F, Cl, Br, I, OH, CH₃,OCH₃, NO₂ NHCHO, CO₂ H, CN, and NR¹¹ R¹², where R¹¹ and R¹² areindependently selected from H and C₁₋₅ alkyl or together with the N atomthey form a cyclic structure XI ##STR29## wherein a is 1-6.
 5. A processaccording to claim 1, wherein R² is 2-pyridyl; R⁸ is methyl, ethyl,t-butyl, or benzyl; R⁹ is H; X¹ is H; and Y is --O--.
 6. A processaccording to claim 1, whereinR² is pyridyl, pyridazinyl, pyrimidinyl,pyrazinyl, thiazolyl, isothiazolyl, methyl-imidazolyl, oxazolyl,isoxazolyl, optionally protected pyrazolyl, optionally protectedimidazolyl, or optionally substituted phenyl; R⁸ is a linear or branchedC₁ -C₆ alkyl, a C₃ -C₈ cycloalkyl, optionally substituted benzyl, oroptionally substituted phenyl; and R⁹ is H, a linear or branched C₁ -C₆alkyl, or CH₂ COR⁴ where R⁴ is an alkyl, a C₃ -C₈ cycloalkyl,2-methylphenyl, 3-methylphenyl, or 4-methylphenyl.